Adding GYP V2 targets for all Polymer code (with a script!).

third_party/polymer/v1_0/gendeps.js

+var fs = require('fs');
+var path = require('path');
+var glob = require('glob').sync;
+
+var ignoreFolders = new Set(['polymer', 'polymer-externs']);
+var srcDir = path.resolve(path.join(__dirname, 'components-chromium'));
+
+var folders = fs.readdirSync(srcDir).filter(function(folder) {
+  return !ignoreFolders.has(folder);
+}).map(function(folder) {
+  return path.join(srcDir, folder);
+});
+
+var chromiumHeader =
+    '# Copyright 2016 The Chromium Authors. All rights reserved.\n' +
+    '# Use of this source code is governed by a BSD-style license that can be\n' +
+    '# found in the LICENSE file.\n';
+
+var ignoreFiles = new Set(['index']);
+function processFolder(folder) {
+
+  var htmlFiles = glob(folder + '/**/*.html').filter(function(file) {
+    return !ignoreFiles.has(path.basename(file, '.html'));
+  });
+  var targets = htmlFiles.map(function(file) {
+    return createTarget(file, detectDependencies(file));
+  });
+  //console.log(
+  //    JSON.stringify({targets: targets}, undefined, 2));
+  var compiledResourcesContents = chromiumHeader +
+      JSON.stringify({targets: targets}, undefined, 2).replace(/"/g, '\'');
+  fs.writeFileSync(
+      path.join(folder, 'compiled_resources2.gyp'),
+      compiledResourcesContents);
+}
+
+function detectDependencies(file) {
+  var fileContents = fs.readFileSync(file, {encoding: 'utf8'});
+  var regexp = /^<link rel="import" href="(.*)"/;

[Dan Beam, 2016/02/16 07:01:08]

BeautifulSoup is a better candidate for this, IMO:
https://codereview.chromium.org/1702553002/

+  var lines = fileContents.split('\n');
+  var dependencies = [];
+  lines.forEach(function(line) {
+    var results = regexp.exec(line);
+    if (results && results[1].indexOf('/polymer.html') == -1) {
+      dependencies.push(results[1]);
+    }
+  });
+  return dependencies;
+}
+
+
+folders.forEach(processFolder);
+
+function fileToTarget(file) {
+  return path.basename(file, '.html') + '-extracted';
+}
+
+function createTarget(file, fileDependencies) {
+  var gypDependencies = fileDependencies.map(function(dep) {
+    var parts = dep.split(path.sep);
+    if (parts.length == 1) {
+      return fileToTarget(parts[0]);
+    }
+    return path.join(parts[0], parts[1], 'compiled_resources2.gyp:') +
+        fileToTarget(parts[parts.length -1]);
+  });
+  var obj = {
+    target_name: fileToTarget(file),
+  };
+  if (gypDependencies.length > 0) {
+    obj.dependencies = gypDependencies;
+  }
+  obj.includes = ['../../../../closure_compiler/compile_js2.gypi'];
+  return obj;
+}