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/syntax/create.js b/node_modules/css-tree/lib/syntax/create.js
new file mode 100644
index 0000000..68b6d16
--- /dev/null
+++ b/node_modules/css-tree/lib/syntax/create.js
@@ -0,0 +1,77 @@
+var List = require('../common/List');
+var SyntaxError = require('../common/SyntaxError');
+var TokenStream = require('../common/TokenStream');
+var Lexer = require('../lexer/Lexer');
+var definitionSyntax = require('../definition-syntax');
+var tokenize = require('../tokenizer');
+var createParser = require('../parser/create');
+var createGenerator = require('../generator/create');
+var createConvertor = require('../convertor/create');
+var createWalker = require('../walker/create');
+var clone = require('../utils/clone');
+var names = require('../utils/names');
+var mix = require('./config/mix');
+
+function createSyntax(config) {
+    var parse = createParser(config);
+    var walk = createWalker(config);
+    var generate = createGenerator(config);
+    var convert = createConvertor(walk);
+
+    var syntax = {
+        List: List,
+        SyntaxError: SyntaxError,
+        TokenStream: TokenStream,
+        Lexer: Lexer,
+
+        vendorPrefix: names.vendorPrefix,
+        keyword: names.keyword,
+        property: names.property,
+        isCustomProperty: names.isCustomProperty,
+
+        definitionSyntax: definitionSyntax,
+        lexer: null,
+        createLexer: function(config) {
+            return new Lexer(config, syntax, syntax.lexer.structure);
+        },
+
+        tokenize: tokenize,
+        parse: parse,
+        walk: walk,
+        generate: generate,
+
+        find: walk.find,
+        findLast: walk.findLast,
+        findAll: walk.findAll,
+
+        clone: clone,
+        fromPlainObject: convert.fromPlainObject,
+        toPlainObject: convert.toPlainObject,
+
+        createSyntax: function(config) {
+            return createSyntax(mix({}, config));
+        },
+        fork: function(extension) {
+            var base = mix({}, config); // copy of config
+            return createSyntax(
+                typeof extension === 'function'
+                    ? extension(base, Object.assign)
+                    : mix(base, extension)
+            );
+        }
+    };
+
+    syntax.lexer = new Lexer({
+        generic: true,
+        types: config.types,
+        atrules: config.atrules,
+        properties: config.properties,
+        node: config.node
+    }, syntax);
+
+    return syntax;
+};
+
+exports.create = function(config) {
+    return createSyntax(mix({}, config));
+};