web_dev_style: Fix errors in new directories and enable PRESUBMIT

ui/webui/resources/PRESUBMIT.py

Index: ui/webui/resources/PRESUBMIT.py
diff --git a/ui/webui/resources/PRESUBMIT.py b/ui/webui/resources/PRESUBMIT.py
index 813f5fdc875e6c899e7e3cb38e80aa51835ac510..ec4af5971315e50f4e200de1270e6eb40c911eea 100644
--- a/ui/webui/resources/PRESUBMIT.py
+++ b/ui/webui/resources/PRESUBMIT.py
@@ -59,4 +59,16 @@ def _CommonChecks(input_api, output_api):
   results += _CheckForTranslations(input_api, output_api)
   results += input_api.canned_checks.CheckPatchFormatted(input_api, output_api,
                                                          check_js=True)
+  try:
+    import sys
+    old_sys_path = sys.path
+    cwd = input_api.PresubmitLocalPath()
+    sys.path += [input_api.os_path.join(cwd, '..', '..', '..', 'tools')]
+    from web_dev_style import presubmit_support
+    BLACKLIST = ['ui/webui/resources/js/analytics.js',
+                 'ui/webui/resources/js/jstemplate_compiled.js']
+    file_filter = lambda f: f.LocalPath() not in BLACKLIST
+    results += presubmit_support.CheckStyle(input_api, output_api, file_filter)
+  finally:
+    sys.path = old_sys_path
   return results