Add packages to optimize svgs dynamically

These packages will be used to dynamically optimize SVG images
during the build.

R=jacktfranklin@chromium.org

Bug: 1216402
Change-Id: I04e95aa7d79c9d67beaf8a7861182c52b16b7d0f
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2939992
Reviewed-by: Jack Franklin <jacktfranklin@chromium.org>
Commit-Queue: Tim van der Lippe <tvanderlippe@chromium.org>
diff --git a/node_modules/css-tree/lib/lexer/match.js b/node_modules/css-tree/lib/lexer/match.js
new file mode 100644
index 0000000..333ed7f
--- /dev/null
+++ b/node_modules/css-tree/lib/lexer/match.js
@@ -0,0 +1,639 @@
+var hasOwnProperty = Object.prototype.hasOwnProperty;
+var matchGraph = require('./match-graph');
+var MATCH = matchGraph.MATCH;
+var MISMATCH = matchGraph.MISMATCH;
+var DISALLOW_EMPTY = matchGraph.DISALLOW_EMPTY;
+var TYPE = require('../tokenizer/const').TYPE;
+
+var STUB = 0;
+var TOKEN = 1;
+var OPEN_SYNTAX = 2;
+var CLOSE_SYNTAX = 3;
+
+var EXIT_REASON_MATCH = 'Match';
+var EXIT_REASON_MISMATCH = 'Mismatch';
+var EXIT_REASON_ITERATION_LIMIT = 'Maximum iteration number exceeded (please fill an issue on https://github.com/csstree/csstree/issues)';
+
+var ITERATION_LIMIT = 15000;
+var totalIterationCount = 0;
+
+function reverseList(list) {
+    var prev = null;
+    var next = null;
+    var item = list;
+
+    while (item !== null) {
+        next = item.prev;
+        item.prev = prev;
+        prev = item;
+        item = next;
+    }
+
+    return prev;
+}
+
+function areStringsEqualCaseInsensitive(testStr, referenceStr) {
+    if (testStr.length !== referenceStr.length) {
+        return false;
+    }
+
+    for (var i = 0; i < testStr.length; i++) {
+        var testCode = testStr.charCodeAt(i);
+        var referenceCode = referenceStr.charCodeAt(i);
+
+        // testCode.toLowerCase() for U+0041 LATIN CAPITAL LETTER A (A) .. U+005A LATIN CAPITAL LETTER Z (Z).
+        if (testCode >= 0x0041 && testCode <= 0x005A) {
+            testCode = testCode | 32;
+        }
+
+        if (testCode !== referenceCode) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+function isContextEdgeDelim(token) {
+    if (token.type !== TYPE.Delim) {
+        return false;
+    }
+
+    // Fix matching for unicode-range: U+30??, U+FF00-FF9F
+    // Probably we need to check out previous match instead
+    return token.value !== '?';
+}
+
+function isCommaContextStart(token) {
+    if (token === null) {
+        return true;
+    }
+
+    return (
+        token.type === TYPE.Comma ||
+        token.type === TYPE.Function ||
+        token.type === TYPE.LeftParenthesis ||
+        token.type === TYPE.LeftSquareBracket ||
+        token.type === TYPE.LeftCurlyBracket ||
+        isContextEdgeDelim(token)
+    );
+}
+
+function isCommaContextEnd(token) {
+    if (token === null) {
+        return true;
+    }
+
+    return (
+        token.type === TYPE.RightParenthesis ||
+        token.type === TYPE.RightSquareBracket ||
+        token.type === TYPE.RightCurlyBracket ||
+        token.type === TYPE.Delim
+    );
+}
+
+function internalMatch(tokens, state, syntaxes) {
+    function moveToNextToken() {
+        do {
+            tokenIndex++;
+            token = tokenIndex < tokens.length ? tokens[tokenIndex] : null;
+        } while (token !== null && (token.type === TYPE.WhiteSpace || token.type === TYPE.Comment));
+    }
+
+    function getNextToken(offset) {
+        var nextIndex = tokenIndex + offset;
+
+        return nextIndex < tokens.length ? tokens[nextIndex] : null;
+    }
+
+    function stateSnapshotFromSyntax(nextState, prev) {
+        return {
+            nextState: nextState,
+            matchStack: matchStack,
+            syntaxStack: syntaxStack,
+            thenStack: thenStack,
+            tokenIndex: tokenIndex,
+            prev: prev
+        };
+    }
+
+    function pushThenStack(nextState) {
+        thenStack = {
+            nextState: nextState,
+            matchStack: matchStack,
+            syntaxStack: syntaxStack,
+            prev: thenStack
+        };
+    }
+
+    function pushElseStack(nextState) {
+        elseStack = stateSnapshotFromSyntax(nextState, elseStack);
+    }
+
+    function addTokenToMatch() {
+        matchStack = {
+            type: TOKEN,
+            syntax: state.syntax,
+            token: token,
+            prev: matchStack
+        };
+
+        moveToNextToken();
+        syntaxStash = null;
+
+        if (tokenIndex > longestMatch) {
+            longestMatch = tokenIndex;
+        }
+    }
+
+    function openSyntax() {
+        syntaxStack = {
+            syntax: state.syntax,
+            opts: state.syntax.opts || (syntaxStack !== null && syntaxStack.opts) || null,
+            prev: syntaxStack
+        };
+
+        matchStack = {
+            type: OPEN_SYNTAX,
+            syntax: state.syntax,
+            token: matchStack.token,
+            prev: matchStack
+        };
+    }
+
+    function closeSyntax() {
+        if (matchStack.type === OPEN_SYNTAX) {
+            matchStack = matchStack.prev;
+        } else {
+            matchStack = {
+                type: CLOSE_SYNTAX,
+                syntax: syntaxStack.syntax,
+                token: matchStack.token,
+                prev: matchStack
+            };
+        }
+
+        syntaxStack = syntaxStack.prev;
+    }
+
+    var syntaxStack = null;
+    var thenStack = null;
+    var elseStack = null;
+
+    // null – stashing allowed, nothing stashed
+    // false – stashing disabled, nothing stashed
+    // anithing else – fail stashable syntaxes, some syntax stashed
+    var syntaxStash = null;
+
+    var iterationCount = 0; // count iterations and prevent infinite loop
+    var exitReason = null;
+
+    var token = null;
+    var tokenIndex = -1;
+    var longestMatch = 0;
+    var matchStack = {
+        type: STUB,
+        syntax: null,
+        token: null,
+        prev: null
+    };
+
+    moveToNextToken();
+
+    while (exitReason === null && ++iterationCount < ITERATION_LIMIT) {
+        // function mapList(list, fn) {
+        //     var result = [];
+        //     while (list) {
+        //         result.unshift(fn(list));
+        //         list = list.prev;
+        //     }
+        //     return result;
+        // }
+        // console.log('--\n',
+        //     '#' + iterationCount,
+        //     require('util').inspect({
+        //         match: mapList(matchStack, x => x.type === TOKEN ? x.token && x.token.value : x.syntax ? ({ [OPEN_SYNTAX]: '<', [CLOSE_SYNTAX]: '</' }[x.type] || x.type) + '!' + x.syntax.name : null),
+        //         token: token && token.value,
+        //         tokenIndex,
+        //         syntax: syntax.type + (syntax.id ? ' #' + syntax.id : '')
+        //     }, { depth: null })
+        // );
+        switch (state.type) {
+            case 'Match':
+                if (thenStack === null) {
+                    // turn to MISMATCH when some tokens left unmatched
+                    if (token !== null) {
+                        // doesn't mismatch if just one token left and it's an IE hack
+                        if (tokenIndex !== tokens.length - 1 || (token.value !== '\\0' && token.value !== '\\9')) {
+                            state = MISMATCH;
+                            break;
+                        }
+                    }
+
+                    // break the main loop, return a result - MATCH
+                    exitReason = EXIT_REASON_MATCH;
+                    break;
+                }
+
+                // go to next syntax (`then` branch)
+                state = thenStack.nextState;
+
+                // check match is not empty
+                if (state === DISALLOW_EMPTY) {
+                    if (thenStack.matchStack === matchStack) {
+                        state = MISMATCH;
+                        break;
+                    } else {
+                        state = MATCH;
+                    }
+                }
+
+                // close syntax if needed
+                while (thenStack.syntaxStack !== syntaxStack) {
+                    closeSyntax();
+                }
+
+                // pop stack
+                thenStack = thenStack.prev;
+                break;
+
+            case 'Mismatch':
+                // when some syntax is stashed
+                if (syntaxStash !== null && syntaxStash !== false) {
+                    // there is no else branches or a branch reduce match stack
+                    if (elseStack === null || tokenIndex > elseStack.tokenIndex) {
+                        // restore state from the stash
+                        elseStack = syntaxStash;
+                        syntaxStash = false; // disable stashing
+                    }
+                } else if (elseStack === null) {
+                    // no else branches -> break the main loop
+                    // return a result - MISMATCH
+                    exitReason = EXIT_REASON_MISMATCH;
+                    break;
+                }
+
+                // go to next syntax (`else` branch)
+                state = elseStack.nextState;
+
+                // restore all the rest stack states
+                thenStack = elseStack.thenStack;
+                syntaxStack = elseStack.syntaxStack;
+                matchStack = elseStack.matchStack;
+                tokenIndex = elseStack.tokenIndex;
+                token = tokenIndex < tokens.length ? tokens[tokenIndex] : null;
+
+                // pop stack
+                elseStack = elseStack.prev;
+                break;
+
+            case 'MatchGraph':
+                state = state.match;
+                break;
+
+            case 'If':
+                // IMPORTANT: else stack push must go first,
+                // since it stores the state of thenStack before changes
+                if (state.else !== MISMATCH) {
+                    pushElseStack(state.else);
+                }
+
+                if (state.then !== MATCH) {
+                    pushThenStack(state.then);
+                }
+
+                state = state.match;
+                break;
+
+            case 'MatchOnce':
+                state = {
+                    type: 'MatchOnceBuffer',
+                    syntax: state,
+                    index: 0,
+                    mask: 0
+                };
+                break;
+
+            case 'MatchOnceBuffer':
+                var terms = state.syntax.terms;
+
+                if (state.index === terms.length) {
+                    // no matches at all or it's required all terms to be matched
+                    if (state.mask === 0 || state.syntax.all) {
+                        state = MISMATCH;
+                        break;
+                    }
+
+                    // a partial match is ok
+                    state = MATCH;
+                    break;
+                }
+
+                // all terms are matched
+                if (state.mask === (1 << terms.length) - 1) {
+                    state = MATCH;
+                    break;
+                }
+
+                for (; state.index < terms.length; state.index++) {
+                    var matchFlag = 1 << state.index;
+
+                    if ((state.mask & matchFlag) === 0) {
+                        // IMPORTANT: else stack push must go first,
+                        // since it stores the state of thenStack before changes
+                        pushElseStack(state);
+                        pushThenStack({
+                            type: 'AddMatchOnce',
+                            syntax: state.syntax,
+                            mask: state.mask | matchFlag
+                        });
+
+                        // match
+                        state = terms[state.index++];
+                        break;
+                    }
+                }
+                break;
+
+            case 'AddMatchOnce':
+                state = {
+                    type: 'MatchOnceBuffer',
+                    syntax: state.syntax,
+                    index: 0,
+                    mask: state.mask
+                };
+                break;
+
+            case 'Enum':
+                if (token !== null) {
+                    var name = token.value.toLowerCase();
+
+                    // drop \0 and \9 hack from keyword name
+                    if (name.indexOf('\\') !== -1) {
+                        name = name.replace(/\\[09].*$/, '');
+                    }
+
+                    if (hasOwnProperty.call(state.map, name)) {
+                        state = state.map[name];
+                        break;
+                    }
+                }
+
+                state = MISMATCH;
+                break;
+
+            case 'Generic':
+                var opts = syntaxStack !== null ? syntaxStack.opts : null;
+                var lastTokenIndex = tokenIndex + Math.floor(state.fn(token, getNextToken, opts));
+
+                if (!isNaN(lastTokenIndex) && lastTokenIndex > tokenIndex) {
+                    while (tokenIndex < lastTokenIndex) {
+                        addTokenToMatch();
+                    }
+
+                    state = MATCH;
+                } else {
+                    state = MISMATCH;
+                }
+
+                break;
+
+            case 'Type':
+            case 'Property':
+                var syntaxDict = state.type === 'Type' ? 'types' : 'properties';
+                var dictSyntax = hasOwnProperty.call(syntaxes, syntaxDict) ? syntaxes[syntaxDict][state.name] : null;
+
+                if (!dictSyntax || !dictSyntax.match) {
+                    throw new Error(
+                        'Bad syntax reference: ' +
+                        (state.type === 'Type'
+                            ? '<' + state.name + '>'
+                            : '<\'' + state.name + '\'>')
+                    );
+                }
+
+                // stash a syntax for types with low priority
+                if (syntaxStash !== false && token !== null && state.type === 'Type') {
+                    var lowPriorityMatching =
+                        // https://drafts.csswg.org/css-values-4/#custom-idents
+                        // When parsing positionally-ambiguous keywords in a property value, a <custom-ident> production
+                        // can only claim the keyword if no other unfulfilled production can claim it.
+                        (state.name === 'custom-ident' && token.type === TYPE.Ident) ||
+
+                        // https://drafts.csswg.org/css-values-4/#lengths
+                        // ... if a `0` could be parsed as either a <number> or a <length> in a property (such as line-height),
+                        // it must parse as a <number>
+                        (state.name === 'length' && token.value === '0');
+
+                    if (lowPriorityMatching) {
+                        if (syntaxStash === null) {
+                            syntaxStash = stateSnapshotFromSyntax(state, elseStack);
+                        }
+
+                        state = MISMATCH;
+                        break;
+                    }
+                }
+
+                openSyntax();
+                state = dictSyntax.match;
+                break;
+
+            case 'Keyword':
+                var name = state.name;
+
+                if (token !== null) {
+                    var keywordName = token.value;
+
+                    // drop \0 and \9 hack from keyword name
+                    if (keywordName.indexOf('\\') !== -1) {
+                        keywordName = keywordName.replace(/\\[09].*$/, '');
+                    }
+
+                    if (areStringsEqualCaseInsensitive(keywordName, name)) {
+                        addTokenToMatch();
+                        state = MATCH;
+                        break;
+                    }
+                }
+
+                state = MISMATCH;
+                break;
+
+            case 'AtKeyword':
+            case 'Function':
+                if (token !== null && areStringsEqualCaseInsensitive(token.value, state.name)) {
+                    addTokenToMatch();
+                    state = MATCH;
+                    break;
+                }
+
+                state = MISMATCH;
+                break;
+
+            case 'Token':
+                if (token !== null && token.value === state.value) {
+                    addTokenToMatch();
+                    state = MATCH;
+                    break;
+                }
+
+                state = MISMATCH;
+                break;
+
+            case 'Comma':
+                if (token !== null && token.type === TYPE.Comma) {
+                    if (isCommaContextStart(matchStack.token)) {
+                        state = MISMATCH;
+                    } else {
+                        addTokenToMatch();
+                        state = isCommaContextEnd(token) ? MISMATCH : MATCH;
+                    }
+                } else {
+                    state = isCommaContextStart(matchStack.token) || isCommaContextEnd(token) ? MATCH : MISMATCH;
+                }
+
+                break;
+
+            case 'String':
+                var string = '';
+
+                for (var lastTokenIndex = tokenIndex; lastTokenIndex < tokens.length && string.length < state.value.length; lastTokenIndex++) {
+                    string += tokens[lastTokenIndex].value;
+                }
+
+                if (areStringsEqualCaseInsensitive(string, state.value)) {
+                    while (tokenIndex < lastTokenIndex) {
+                        addTokenToMatch();
+                    }
+
+                    state = MATCH;
+                } else {
+                    state = MISMATCH;
+                }
+
+                break;
+
+            default:
+                throw new Error('Unknown node type: ' + state.type);
+        }
+    }
+
+    totalIterationCount += iterationCount;
+
+    switch (exitReason) {
+        case null:
+            console.warn('[csstree-match] BREAK after ' + ITERATION_LIMIT + ' iterations');
+            exitReason = EXIT_REASON_ITERATION_LIMIT;
+            matchStack = null;
+            break;
+
+        case EXIT_REASON_MATCH:
+            while (syntaxStack !== null) {
+                closeSyntax();
+            }
+            break;
+
+        default:
+            matchStack = null;
+    }
+
+    return {
+        tokens: tokens,
+        reason: exitReason,
+        iterations: iterationCount,
+        match: matchStack,
+        longestMatch: longestMatch
+    };
+}
+
+function matchAsList(tokens, matchGraph, syntaxes) {
+    var matchResult = internalMatch(tokens, matchGraph, syntaxes || {});
+
+    if (matchResult.match !== null) {
+        var item = reverseList(matchResult.match).prev;
+
+        matchResult.match = [];
+
+        while (item !== null) {
+            switch (item.type) {
+                case STUB:
+                    break;
+
+                case OPEN_SYNTAX:
+                case CLOSE_SYNTAX:
+                    matchResult.match.push({
+                        type: item.type,
+                        syntax: item.syntax
+                    });
+                    break;
+
+                default:
+                    matchResult.match.push({
+                        token: item.token.value,
+                        node: item.token.node
+                    });
+                    break;
+            }
+
+            item = item.prev;
+        }
+    }
+
+    return matchResult;
+}
+
+function matchAsTree(tokens, matchGraph, syntaxes) {
+    var matchResult = internalMatch(tokens, matchGraph, syntaxes || {});
+
+    if (matchResult.match === null) {
+        return matchResult;
+    }
+
+    var item = matchResult.match;
+    var host = matchResult.match = {
+        syntax: matchGraph.syntax || null,
+        match: []
+    };
+    var hostStack = [host];
+
+    // revert a list and start with 2nd item since 1st is a stub item
+    item = reverseList(item).prev;
+
+    // build a tree
+    while (item !== null) {
+        switch (item.type) {
+            case OPEN_SYNTAX:
+                host.match.push(host = {
+                    syntax: item.syntax,
+                    match: []
+                });
+                hostStack.push(host);
+                break;
+
+            case CLOSE_SYNTAX:
+                hostStack.pop();
+                host = hostStack[hostStack.length - 1];
+                break;
+
+            default:
+                host.match.push({
+                    syntax: item.syntax || null,
+                    token: item.token.value,
+                    node: item.token.node
+                });
+        }
+
+        item = item.prev;
+    }
+
+    return matchResult;
+}
+
+module.exports = {
+    matchAsList: matchAsList,
+    matchAsTree: matchAsTree,
+    getTotalIterationCount: function() {
+        return totalIterationCount;
+    }
+};