WebUI: Generate manifest files from optimize_webui

Change optimize_webui to generate a manifest file when an |out_manifest|
argument is provided.

Started from:
https://chromium-review.googlesource.com/c/chromium/src/+/2443211
by dpapad@

Bug: 1132403
Change-Id: Ia80c4d2c004ec4414c500c407e2d2c8d187ff847
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2463962Reviewed-by: dpapad <dpapad@chromium.org>
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#815777}

chrome/browser/resources/optimize_webui.gni

@@ -86,6 +86,14 @@ template("optimize_webui") {
       inputs += [ "//chrome/browser/resources/tools/rollup_plugin.js" ]
       args += [ "--js_module_in_files" ] + invoker.js_module_in_files
     }
+
+    if (defined(invoker.out_manifest)) {
+      args += [
+        "--out-manifest",
+        rebase_path(invoker.out_manifest, root_build_dir),
+      ]
+      outputs += [ invoker.out_manifest ]
+    }
   }
 }
 

chrome/browser/resources/optimize_webui.py

@@ -380,6 +380,7 @@ def main(argv):
   parser.add_argument('--js_out_files', nargs='*', required=True)
   parser.add_argument('--out_folder', required=True)
   parser.add_argument('--js_module_in_files', nargs='*')
+  parser.add_argument('--out-manifest')
   parser.add_argument('--gen_dir_relpath', default='gen', help='Path of the '
       'gen directory relative to the out/. If running in the default '
       'toolchain, the path is gen, otherwise $toolchain_name/gen')
@@ -411,6 +412,16 @@ def main(argv):
         'polymer-bundler could not find files for the following URLs:\n' +
         '\n'.join(manifest['_missing']))
 
+
+  # Output a manifest file that will be used to auto-generate a grd file later.
+  if args.out_manifest:
+    manifest_data = {}
+    manifest_data['base_dir'] = '%s' % args.out_folder
+    manifest_data['files'] = manifest.keys()
+    manifest_file = open(
+        os.path.normpath(os.path.join(_CWD, args.out_manifest)), 'wb')
+    json.dump(manifest_data, manifest_file)
+
   _update_dep_file(args.input, args, manifest)
 
 

chrome/browser/resources/optimize_webui_test.py

@@ -3,6 +3,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import json
 import optimize_webui
 import os
 import shutil
@@ -10,14 +11,15 @@ import tempfile
 import unittest
 
 
+_CWD = os.getcwd()
 _HERE_DIR = os.path.dirname(__file__)
 
 
 class OptimizeWebUiTest(unittest.TestCase):
   def setUp(self):
-    self._out_folder = None
     self._tmp_dirs = []
     self._tmp_src_dir = None
+    self._out_folder = self._create_tmp_dir()
 
   def tearDown(self):
     for tmp_dir in self._tmp_dirs:
@@ -45,8 +47,6 @@ class OptimizeWebUiTest(unittest.TestCase):
     return open(os.path.join(self._out_folder, file_name), 'r').read()
 
   def _run_optimize(self, input_args):
-    assert not self._out_folder
-    self._out_folder = self._create_tmp_dir()
     # TODO(dbeam): make it possible to _run_optimize twice? Is that useful?
     args = input_args + [
       '--depfile', os.path.join(self._out_folder, 'depfile.d'),
@@ -209,6 +209,7 @@ import './element_in_dir/element_in_dir.js';
     args = [
       '--js_module_in_files', 'ui.js', 'lazy.js',
       '--js_out_files', 'ui.rollup.js', 'lazy.rollup.js', 'shared.rollup.js',
+      '--out-manifest', os.path.join(self._out_folder, 'out_manifest.json'),
     ]
     self._run_optimize(args)
 
@@ -234,5 +235,15 @@ import './element_in_dir/element_in_dir.js';
     depfile_d = self._read_out_file('depfile.d')
     self.assertIn('lazy_element.js', depfile_d)
 
+    manifest = json.loads(self._read_out_file('out_manifest.json'))
+    self.assertEquals(3, len(manifest['files']))
+    self.assertTrue('lazy.rollup.js' in manifest['files'])
+    self.assertTrue('ui.rollup.js' in manifest['files'])
+    self.assertTrue('shared.rollup.js' in manifest['files'])
+
+    self.assertEquals(
+        os.path.relpath(self._out_folder, _CWD).replace('\\', '/'),
+        os.path.relpath(manifest['base_dir'], _CWD).replace('\\', '/'))
+
 if __name__ == '__main__':
   unittest.main()