[Presubmit] check for single quotes in html properties

chrome/browser/web_dev_style/html_checker.py

Index: chrome/browser/web_dev_style/html_checker.py
diff --git a/chrome/browser/web_dev_style/html_checker.py b/chrome/browser/web_dev_style/html_checker.py
index 422b7852185410a6f833185faee07bc96a269034..bd842e278288a9729991f61cbf346907f9276cdd 100644
--- a/chrome/browser/web_dev_style/html_checker.py
+++ b/chrome/browser/web_dev_style/html_checker.py
@@ -44,6 +44,17 @@ class HtmlChecker(object):
     return regex_check.RegexCheck(self.input_api.re, line_number, line, regex,
         'Use the button element instead of <input type="button">')
 
+  def DoNotUseSingleQuotesCheck(self, line_number, line):
+    regex = self.input_api.re.compile("""
+        (<\s*\w*             # The tag name.
+        (?:\s+\w+="[^"]*")*  # There may be some correctly quoted (foo="bar").
+        \s+\w+='[^']*'       # Find incorrectly quoted (foo='bar').
+        [^>]*>)              # To the end of the tag.
+        """,
+        self.input_api.re.VERBOSE)
+    return regex_check.RegexCheck(self.input_api.re, line_number, line, regex,
+        'Use double quotes rather than single quotes in HTML properties')
+
   def I18nContentJavaScriptCaseCheck(self, line_number, line):
     regex = self.input_api.re.compile("""
         (?:^|\s)                      # start of line or whitespace