DevTools: support live coverage

third_party/WebKit/Source/devtools/front_end/sdk/CSSModel.js

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 277 matching lines @@
       this._fireStyleSheetChanged(styleSheetId, edit);
       return true;
     }
 
     Host.userMetrics.actionTaken(Host.UserMetrics.Action.StyleRuleEdited);
     return this._ensureOriginalStyleSheetText(styleSheetId)
         .then(() => this._agent.setKeyframeKey(styleSheetId, range, text, callback.bind(this)))
         .catchException(false);
   }
 
-  startRuleUsageTracking() {
+  startCoverage() {
     this._agent.startRuleUsageTracking();
   }
 
   /**
    * @return {!Promise<!Array<!Protocol.CSS.RuleUsage>>}
    */
-  ruleListPromise() {
-    /**
-     * @param {?string} error
-     * @param {!Array<!Protocol.CSS.RuleUsage>=} ruleUsage
-     * @return {!Array<!Protocol.CSS.RuleUsage>}
-     */
-    function usedRulesCallback(error, ruleUsage) {
-      if (error || !ruleUsage)
-        return [];
-
-      return ruleUsage;
-    }
-
-    return this._agent.stopRuleUsageTracking(usedRulesCallback);
+  takeCoverageDelta() {
+    return this._agent.takeCoverageDelta((error, ruleUsage) => error || !ruleUsage ? [] : ruleUsage);
   }
 
   /**
+   * @return {!Promise}
+   */
+  stopCoverage() {
+    return this._agent.stopRuleUsageTracking();
+  }
+
+  /**
    * @return {!Promise.<!Array.<!SDK.CSSMedia>>}
    */
   mediaQueriesPromise() {
     /**
      * @param {?Protocol.Error} error
      * @param {?Array.<!Protocol.CSS.CSSMedia>} payload
      * @return {!Array.<!SDK.CSSMedia>}
      * @this {!SDK.CSSModel}
      */
     function parsePayload(error, payload) {
@@ skipping 698 matching lines @@
 SDK.CSSModel.InlineStyleResult = class {
   /**
    * @param {?SDK.CSSStyleDeclaration} inlineStyle
    * @param {?SDK.CSSStyleDeclaration} attributesStyle
    */
   constructor(inlineStyle, attributesStyle) {
     this.inlineStyle = inlineStyle;
     this.attributesStyle = attributesStyle;
   }
 };