[WebUI] Fix rest of CSS style nits so I can turn on CSS checker.

chrome/browser/resources/web_dev_style/css_checker.py

 # Copyright (c) 2012 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.
 
 """Presubmit script for Chromium WebUI resources.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into gcl/git cl, and see
 http://www.chromium.org/developers/web-development-style-guide for the rules
 we're checking against here.
@@ skipping 50 matching lines @@
     def braces_have_space_before_and_nothing_after(line):
       return re.search(r'(?:^|\S){|{\s*\S+\s*$', line)
 
     def classes_use_dashes(line):
       # Intentionally dumbed down version of CSS 2.1 grammar for class without
       # non-ASCII, escape chars, or whitespace.
       m = re.search(r'\.(-?[_a-zA-Z0-9-]+).*[,{]\s*$', line)
       return (m and (m.group(1).lower() != m.group(1) or
                      m.group(1).find('_') >= 0))
 
+    # Ignore single frames in a @keyframe, i.e. 0% { margin: 50px; }
+    frame_reg = r'\s*\d+%\s*{\s*[_a-zA-Z0-9-]+:(\s*[_a-zA-Z0-9-]+)+\s*;\s*}\s*'
     def close_brace_on_new_line(line):
-      return (line.find('}') >= 0 and re.search(r'[^ }]', line))
+      return (line.find('}') >= 0 and re.search(r'[^ }]', line) and
+              not re.match(frame_reg, line))
 
     def colons_have_space_after(line):
       return re.search(r':(?!//)\S[^;]+;\s*', line)
 
     def favor_single_quotes(line):
       return line.find('"') >= 0
 
     # Shared between hex_could_be_shorter and rgb_if_not_gray.
     hex_reg = (r'#([a-fA-F0-9]{3}|[a-fA-F0-9]{6})(?=[^_a-zA-Z0-9-]|$)'
                r'(?!.*(?:{.*|,\s*)$)')
     def hex_could_be_shorter(line):
       m = re.search(hex_reg, line)
-      return (m and _collapseable_hex(m.group(1)))
+      return (m and _is_gray(m.group(1)) and _collapseable_hex(m.group(1)))
 
     small_seconds = r'(?:^|[^_a-zA-Z0-9-])(0?\.[0-9]+)s(?!-?[_a-zA-Z0-9-])'
     def milliseconds_for_small_times(line):
       return re.search(small_seconds, line)
 
     def one_rule_per_line(line):
       return re.search(r'[_a-zA-Z0-9-]:(?!//)[^;]+;\s*[^ }]\s*', line)
 
     any_reg = re.compile(r':(?:-webkit-)?any\(.*?\)', re.DOTALL)
     multi_sels = re.compile(r'(?:}[\n\s]*)?([^,]+,(?=[^{}]+?{).*[,{])\s*$',
                             re.MULTILINE)
     def one_selector_per_line(contents):
       errors = []
       for b in re.finditer(multi_sels, re.sub(any_reg, '', contents)):
-        errors.append('    ' + b.group(1).strip())
+        errors.append('    ' + b.group(1).strip().splitlines()[-1:][0])
       return errors
 
     def rgb_if_not_gray(line):
       m = re.search(hex_reg, line)
       return (m and not _is_gray(m.group(1)))
 
     def suggest_ms_from_s(line):
       ms = int(float(re.search(small_seconds, line).group(1)) * 1000)
       return ' (replace with %dms)' % ms
 
@@ skipping 91 matching lines @@
             line = lines[lnum]
             if check['test'](line):
               error = '    ' + line.strip()
               if 'after' in check:
                 error += check['after'](line)
               check_errors.append(error)
           if len(check_errors) > 0:
             file_errors.append('- %s\n%s' %
                 (check['desc'], '\n'.join(check_errors)))
       if file_errors:
-        results.append(self.output_api.PresubmitError(
+        results.append(self.output_api.PresubmitPromptWarning(
             '%s:\n%s' % (f[0], '\n\n'.join(file_errors))))
 
     if results:
       # Add your name if you're here often mucking around in the code.
       authors = ['dbeam@chromium.org']
       results.append(self.output_api.PresubmitNotifyResult(
           'Was the CSS checker useful? Send feedback or hate mail to %s.' %
           ', '.join(authors)))
 
     return results