DevTools: add support for polling for coverage data in CSS agent

third_party/WebKit/Source/core/css/ElementRuleCollector.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc.
  * All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
@@ skipping 360 matching lines @@
   // about "scope".
   MatchRequest matchRequest(ruleSet);
   collectMatchingRules(matchRequest);
   collectMatchingShadowHostRules(matchRequest);
 
   return !m_matchedRules.isEmpty();
 }
 
 void ElementRuleCollector::addMatchedRulesToTracker(
     StyleRuleUsageTracker* tracker) const {
-  for (auto matchedRule : m_matchedRules)
-    tracker->track(matchedRule.ruleData()->rule());
+  for (auto matchedRule : m_matchedRules) {
+    tracker->track(matchedRule.ruleData()->rule(),

[pfeldman, 2017/03/21 18:04:15]

nit: swap parameters :)

+                   matchedRule.parentStyleSheet());
+  }
 }
 
 }  // namespace blink