Add eslint-import-plugin to node_modules

Will be used to make sure no default exports are in DevTools.

The PRESUBMIT.py has been updated to skip running the formatting check
if node_modules files are affected, to workaround crbug.com/1068198.

DISABLE_THIRD_PARTY_CHECK=Add plugin to node_modules

Bug: 1068198
Change-Id: I04d4dc813daa01099f21d40edf47aaefcc0b045f
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2135610
Commit-Queue: Tim van der Lippe <tvanderlippe@chromium.org>
Auto-Submit: Tim van der Lippe <tvanderlippe@chromium.org>
Reviewed-by: Jack Franklin <jacktfranklin@chromium.org>
diff --git a/node_modules/eslint-import-resolver-node/index.js b/node_modules/eslint-import-resolver-node/index.js
new file mode 100644
index 0000000..b5a1537
--- /dev/null
+++ b/node_modules/eslint-import-resolver-node/index.js
@@ -0,0 +1,47 @@
+var resolve = require('resolve')
+  , path = require('path')
+
+var log = require('debug')('eslint-plugin-import:resolver:node')
+
+exports.interfaceVersion = 2
+
+exports.resolve = function (source, file, config) {
+  log('Resolving:', source, 'from:', file)
+  var resolvedPath
+
+  if (resolve.isCore(source)) {
+    log('resolved to core')
+    return { found: true, path: null }
+  }
+
+  try {
+    resolvedPath = resolve.sync(source, opts(file, config))
+    log('Resolved to:', resolvedPath)
+    return { found: true, path: resolvedPath }
+  } catch (err) {
+    log('resolve threw error:', err)
+    return { found: false }
+  }
+}
+
+function opts(file, config) {
+  return Object.assign({
+      // more closely matches Node (#333)
+      // plus 'mjs' for native modules! (#939)
+      extensions: ['.mjs', '.js', '.json'],
+    },
+    config,
+    {
+      // path.resolve will handle paths relative to CWD
+      basedir: path.dirname(path.resolve(file)),
+      packageFilter: packageFilter,
+
+    })
+}
+
+function packageFilter(pkg) {
+  if (pkg['jsnext:main']) {
+    pkg['main'] = pkg['jsnext:main']
+  }
+  return pkg
+}