Update list of resource files to copy from web-platform-tests.

third_party/WebKit/Tools/Scripts/webkitpy/w3c/deps_updater.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Fetches a copy of the latest state of a W3C test repository and commits.
 
 If this script is given the argument --auto-update, it will also attempt to
 upload a CL, triggery try jobs, and make any changes that are required for
 new failing tests before committing.
 """
@@ skipping 33 matching lines @@
             return 1
 
         self.git_cl = GitCL(self.executive, auth_refresh_token_json=options.auth_refresh_token_json)
 
         self.print_('## Noting the current Chromium commit.')
         _, show_ref_output = self.run(['git', 'show-ref', 'HEAD'])
         chromium_commitish = show_ref_output.split()[0]
 
         if options.target == 'wpt':
             import_commitish = self.update(WPT_DEST_NAME, WPT_REPO_URL, options.keep_w3c_repos_around)
-            self._copy_resources_to_wpt()
+            self._copy_resources()
         elif options.target == 'css':
             import_commitish = self.update(CSS_DEST_NAME, CSS_REPO_URL, options.keep_w3c_repos_around)
         else:
             raise AssertionError("Unsupported target %s" % options.target)
 
         has_changes = self.commit_changes_if_needed(chromium_commitish, import_commitish)
         if options.auto_update and has_changes:
             commit_successful = self.do_auto_update()
             if not commit_successful:
                 return 1
@@ skipping 30 matching lines @@
         if self.fs.exists(self.path_from_webkit_base(WPT_DEST_NAME)):
             self.print_('## WebKit/%s exists; aborting.' % WPT_DEST_NAME)
             return False
 
         if self.fs.exists(self.path_from_webkit_base(CSS_DEST_NAME)):
             self.print_('## WebKit/%s repo exists; aborting.' % CSS_DEST_NAME)
             return False
 
         return True
 
-    def _copy_resources_to_wpt(self):
-        """Copies some files over to a newly-updated wpt directory.
+    def _copy_resources(self):
+        """Copies resources from LayoutTests/resources to wpt and vice versa.
 
-        There are some resources in our repository that we use instead of the
-        upstream versions.
+        There are resources from our repository that we use instead of the
+        upstream versions. Conversely, there are also some resources that
+        are copied in the other direction.
+
+        Specifically:
+          - testharnessreport.js contains code needed to integrate our testing
+            with testharness.js; we also want our code to be used for tests
+            in wpt.
+          - TODO(qyearsley, jsbell): Document why other other files are copied,
+            or stop copying them if it's unnecessary.
+
+        If this method is changed, the lists of files expected to be identical
+        in LayoutTests/PRESUBMIT.py should also be changed.
         """
-        resources_to_copy = [
+        resources_to_copy_to_wpt = [
             ('testharnessreport.js', 'resources'),
             ('WebIDLParser.js', 'resources'),
             ('vendor-prefix.js', 'common'),
         ]
-        for filename, wpt_subdir in resources_to_copy:
+        resources_to_copy_from_wpt = [
+            ('idlharness.js', 'resources'),
+            ('testharness.js', 'resources'),
+        ]
+        for filename, wpt_subdir in resources_to_copy_to_wpt:
             source = self.path_from_webkit_base('LayoutTests', 'resources', filename)
             destination = self.path_from_webkit_base('LayoutTests', 'imported', WPT_DEST_NAME, wpt_subdir, filename)
             self.copyfile(source, destination)
             self.run(['git', 'add', destination])
+        for filename, wpt_subdir in resources_to_copy_from_wpt:
+            source = self.path_from_webkit_base('LayoutTests', 'imported', WPT_DEST_NAME, wpt_subdir, filename)
+            destination = self.path_from_webkit_base('LayoutTests', 'resources', filename)
+            self.copyfile(source, destination)
+            self.run(['git', 'add', destination])
 
     def update(self, dest_dir_name, url, keep_w3c_repos_around):
         """Updates an imported repository.
 
         Args:
             dest_dir_name: The destination directory name.
             url: URL of the git repository.
 
         Returns:
             A string for the commit description "<destination>@<commitish>".
@@ skipping 201 matching lines @@
                 email_addresses.add(directory_to_owner[test_dir])
         return sorted(email_addresses)
 
     def write_test_expectations(self):
         self.print_('## Adding test expectations lines to LayoutTests/TestExpectations.')
         script_path = self.path_from_webkit_base('Tools', 'Scripts', 'update-w3c-test-expectations')
         self.run([self.host.executable, script_path])
         message = '\'Modifies TestExpectations and/or downloads new baselines for tests\''
         self.check_run(['git', 'commit', '-a', '-m', message])
         self.git_cl(['upload', '-m', message, '--rietveld'])