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

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

Index: chrome/browser/task_management/providers/web_contents/subframe_task.cc
diff --git a/chrome/browser/task_management/providers/web_contents/subframe_task.cc b/chrome/browser/task_management/providers/web_contents/subframe_task.cc
index fbfbefd82ba24d1cf4ba439806ac511e746ce1f9..258ba7075383af97d46d5d9183514cf2e4885038 100644
--- a/chrome/browser/task_management/providers/web_contents/subframe_task.cc
+++ b/chrome/browser/task_management/providers/web_contents/subframe_task.cc
@@ -30,11 +30,13 @@ base::string16 AdjustTitle(const content::SiteInstance* site_instance) {
 }  // 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.
@@ -53,4 +55,9 @@ void SubframeTask::UpdateFavicon() {
   // 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