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

Source/devtools/front_end/components/ExecutionContextSelector.js

Index: Source/devtools/front_end/components/ExecutionContextSelector.js
diff --git a/Source/devtools/front_end/components/ExecutionContextSelector.js b/Source/devtools/front_end/components/ExecutionContextSelector.js
index 74c40b018ab33d15aee424a98f0659e4e375a969..c073622223c38cf29c55fb39d00ec238efb49312 100644
--- a/Source/devtools/front_end/components/ExecutionContextSelector.js
+++ b/Source/devtools/front_end/components/ExecutionContextSelector.js
@@ -26,8 +26,6 @@ WebInspector.ExecutionContextSelector.prototype = {
         // 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);
         });
@@ -43,7 +41,7 @@ WebInspector.ExecutionContextSelector.prototype = {
             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]);
     },
 
@@ -85,9 +83,14 @@ WebInspector.ExecutionContextSelector.prototype = {
      */
     _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);
+        }
     },
 
     /**
@@ -105,6 +108,8 @@ WebInspector.ExecutionContextSelector.prototype = {
         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];