Task Manager: Make double-clicking on an extension do something useful.

chrome/browser/task_management/providers/web_contents/subframe_task.cc

 // Copyright 2015 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.
 
 #include "chrome/browser/task_management/providers/web_contents/subframe_task.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/grit/generated_resources.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/render_frame_host.h"
@@ skipping 12 matching lines @@
       IDS_TASK_MANAGER_SUBFRAME_INCOGNITO_PREFIX :
       IDS_TASK_MANAGER_SUBFRAME_PREFIX;
 
   return l10n_util::GetStringFUTF16(message_id, base::UTF8ToUTF16(
       site_instance->GetSiteURL().spec()));
 }
 
 }  // namespace
 
 SubframeTask::SubframeTask(content::RenderFrameHost* render_frame_host,
-                           content::WebContents* web_contents)
+                           content::WebContents* web_contents,
+                           RendererTask* main_task)
     : RendererTask(AdjustTitle(render_frame_host->GetSiteInstance()),
                    nullptr,
                    web_contents,
-                   render_frame_host->GetProcess()) {
+                   render_frame_host->GetProcess()),
+      main_task_(main_task) {
   // Note that we didn't get the RenderProcessHost from the WebContents, but
   // rather from the RenderFrameHost. Out-of-process iframes reside on
   // different processes than that of their main frame.
 }
 
 SubframeTask::~SubframeTask() {
 }
 
 void SubframeTask::UpdateTitle() {
   // This will be called when the title changes on the WebContents's main frame,
   // but this Task represents other frames, so we don't care.
 }
 
 void SubframeTask::UpdateFavicon() {
   // This will be called when the favicon changes on the WebContents's main
   // frame, but this Task represents other frames, so we don't care.
 }
 
+void SubframeTask::Activate() {
+  // Activate the root task.
+  main_task_->Activate();
+}
+
 }  // namespace task_management