DevTools: add coverage snapshots

third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js

Index: third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js
diff --git a/third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js b/third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js
index 27fba039c99e2173483ca04bdb9b00b125f71ccb..1e0cf10ec8589c2e39f414bf55150598636bb4a6 100644
--- a/third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js
+++ b/third_party/WebKit/Source/devtools/front_end/coverage/CoverageView.js
@@ -39,6 +39,7 @@ Coverage.CoverageView = class extends UI.VBox {
     this._toggleRecordAction =
         /** @type {!UI.Action }*/ (UI.actionRegistry.action('coverage.toggle-recording'));
     topToolbar.appendToolbarItem(UI.Toolbar.createActionButton(this._toggleRecordAction));
+    topToolbar.appendToolbarItem(UI.Toolbar.createActionButtonForId('coverage.take-snapshot'));
 
     var clearButton = new UI.ToolbarButton(Common.UIString('Clear all'), 'largeicon-clear');
     clearButton.addEventListener(UI.ToolbarButton.Events.Click, this._reset.bind(this));
@@ -88,6 +89,26 @@ Coverage.CoverageView = class extends UI.VBox {
     this._progressElement.textContent = Common.UIString('Recording...');
   }
 
+  async _takeSnapshot() {
+    this._reset();
+    var mainTarget = SDK.targetManager.mainTarget();
+    var profilerAgent = mainTarget && mainTarget.profilerAgent();
+    if (!profilerAgent)
+      return [];
+    var debuggerModel = /** @type !SDK.DebuggerModel */ (SDK.DebuggerModel.fromTarget(mainTarget));
+    var cssModel = mainTarget.model(SDK.CSSModel);
+    if (!cssModel)
+      return;
+
+    cssModel.startRuleUsageTracking();
+    this._progressElement.textContent = Common.UIString('Taking a snapshot...');
+    var cssCoverageInfoPromise = this._stopCSSCoverage();
+    var jsCoverageRawData = await profilerAgent.getBestEffortCoverage((error, result) => error ? [] : result);
+    var jsCoverageInfo = await Coverage.CoverageView._processJSCoverage(debuggerModel, jsCoverageRawData);
+    var cssCoverageInfo = await cssCoverageInfoPromise;
+    this._updateViews(cssCoverageInfo.concat(jsCoverageInfo));
+  }
+
   async _stopRecording() {
     this._toggleRecordAction.setToggled(false);
     this._progressElement.textContent = Common.UIString('Fetching results...');
@@ -349,7 +370,7 @@ Coverage.CoverageView.LineDecorator.type = 'coverage';
 /**
  * @implements {UI.ActionDelegate}
  */
-Coverage.CoverageView.RecordActionDelegate = class {
+Coverage.CoverageView.ActionDelegate = class {
   /**
    * @override
    * @param {!UI.Context} context
@@ -358,10 +379,22 @@ Coverage.CoverageView.RecordActionDelegate = class {
    */
   handleAction(context, actionId) {
     var coverageViewId = 'coverage';
+
     UI.viewManager.showView(coverageViewId)
         .then(() => UI.viewManager.view(coverageViewId).widget())
-        .then(widget => /** @type !Coverage.CoverageView} */ (widget)._toggleRecording());
+        .then(widget => this._handleActionOnWidget(/** @type !Coverage.CoverageView} */ (widget), actionId));
 
     return true;
   }
+
+  /**
+   * @param {!Coverage.CoverageView} widget
+   * @param {string} actionId
+   */
+  _handleActionOnWidget(widget, actionId) {
+    if (actionId === 'coverage.toggle-recording')
+      widget._toggleRecording();
+    else if (actionId === 'coverage.take-snapshot')
+      widget._takeSnapshot();
+  }
 };