DevTools: Fix the way executionContext and target are selected in worker frontend.

Source/devtools/front_end/components/ExecutionContextSelector.js

 // Copyright 2014 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.
 
 /**
  * @constructor
  * @implements {WebInspector.TargetManager.Observer}
  */
 WebInspector.ExecutionContextSelector = function()
 {
     WebInspector.targetManager.observeTargets(this);
     WebInspector.context.addFlavorChangeListener(WebInspector.ExecutionContext, this._executionContextChanged, this);
     WebInspector.context.addFlavorChangeListener(WebInspector.Target, this._targetChanged, this);
 
     WebInspector.targetManager.addModelListener(WebInspector.RuntimeModel, WebInspector.RuntimeModel.Events.ExecutionContextCreated, this._onExecutionContextCreated, this);
     WebInspector.targetManager.addModelListener(WebInspector.RuntimeModel, WebInspector.RuntimeModel.Events.ExecutionContextDestroyed, this._onExecutionContextDestroyed, this);
 }
 
 WebInspector.ExecutionContextSelector.prototype = {
 
     /**
      * @param {!WebInspector.Target} target
      */
     targetAdded: function(target)
     {
         // Defer selecting default target since we need all clients to get their
         // targetAdded notifications first.
         setImmediate(function() {
-            // FIXME(413886): Execution context for the main thread on the service/shared worker shadow page
-            // should never be sent to frontend. The worker forntend check below could be removed once this is fixed.
             if (!WebInspector.context.flavor(WebInspector.Target) || WebInspector.isWorkerFrontend())
                 WebInspector.context.setFlavor(WebInspector.Target, target);
         });
     },
 
     /**
      * @param {!WebInspector.Target} target
      */
     targetRemoved: function(target)
     {
         var currentExecutionContext = WebInspector.context.flavor(WebInspector.ExecutionContext);
         if (currentExecutionContext && currentExecutionContext.target() === target)
             this._currentExecutionContextGone();
 
         var targets = WebInspector.targetManager.targets();
-        if (WebInspector.context.flavor(WebInspector.Target) === target && targets.length)
+        if (WebInspector.context.flavor(WebInspector.Target) === target && targets.length && !WebInspector.isWorkerFrontend())
             WebInspector.context.setFlavor(WebInspector.Target, targets[0]);
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _executionContextChanged: function(event)
     {
         var newContext = /** @type {?WebInspector.ExecutionContext} */ (event.data);
         if (newContext)
@@ skipping 21 matching lines @@
                 newContext = executionContexts[i];
         }
         WebInspector.context.setFlavor(WebInspector.ExecutionContext, newContext);
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _onExecutionContextCreated: function(event)
     {
-        var executionContext = /** @type {!WebInspector.ExecutionContext}*/ (event.data);
-        if (!WebInspector.context.flavor(WebInspector.ExecutionContext))
-            WebInspector.context.setFlavor(WebInspector.ExecutionContext, executionContext);
+        var executionContext = /** @type {!WebInspector.ExecutionContext} */ (event.data);
+
+        if (!WebInspector.context.flavor(WebInspector.ExecutionContext)) {
+            // FIXME(413886): Execution context for the main thread on the service/shared worker shadow page
+            // should never be sent to frontend. The worker frontend check below could be removed once this is fixed.
+            if (!WebInspector.isWorkerFrontend() || executionContext.target() !== WebInspector.targetManager.mainTarget())
+                WebInspector.context.setFlavor(WebInspector.ExecutionContext, executionContext);
+        }
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _onExecutionContextDestroyed: function(event)
     {
         var executionContext = /** @type {!WebInspector.ExecutionContext}*/ (event.data);
         if (WebInspector.context.flavor(WebInspector.ExecutionContext) === executionContext)
             this._currentExecutionContextGone();
     },
 
     _currentExecutionContextGone: function()
     {
         var targets = WebInspector.targetManager.targets();
         var newContext = null;
         for (var i = 0; i < targets.length; ++i) {
+            if (WebInspector.isWorkerFrontend() && targets[i] === WebInspector.targetManager.mainTarget())
+                continue;
             var executionContexts = targets[i].runtimeModel.executionContexts();
             if (executionContexts.length) {
                 newContext = executionContexts[0];
                 break;
             }
         }
         WebInspector.context.setFlavor(WebInspector.ExecutionContext, newContext);
     }
 
 }
@@ skipping 11 matching lines @@
         completionsReadyCallback([]);
         return;
     }
 
     // Pass less stop characters to rangeOfWord so the range will be a more complete expression.
     var expressionRange = wordRange.startContainer.rangeOfWord(wordRange.startOffset, " =:[({;,!+-*/&|^<>", proxyElement, "backward");
     var expressionString = expressionRange.toString();
     var prefix = wordRange.toString();
     executionContext.completionsForExpression(expressionString, prefix, force, completionsReadyCallback);
 }