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

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

Index: chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
diff --git a/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc b/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
index db1f81bcf6a442d90ec4d39ae2ea50d039f5f59d..f6862a33f3dd7e1330d7d9d3df792f75de86e2c4 100644
--- a/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
+++ b/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
@@ -230,7 +230,9 @@ void WebContentsEntry::CreateTaskForFrame(RenderFrameHost* render_frame_host) {
       new_task = tag->CreateTask();
       main_frame_site_instance_ = site_instance;
     } else {
-      new_task = new SubframeTask(render_frame_host, web_contents());
+      new_task =
+          new SubframeTask(render_frame_host, web_contents(),
+                           GetTaskForFrame(web_contents()->GetMainFrame()));

[afakhry, 2016/05/25 20:07:09]

I hope the task of the main frame gets created before its subframe tasks. Is
that guaranteed?

[ncarter (slow), 2016/05/25 20:34:23]

Yes; the way we use WebContentsObserver guarantees this (in general, creation
and ForEachFrame guarantee top-down, and deletion is guaranteed to be
bottom-up.) WebContentsObserverSanityChecker enforces these assumptions.

     }
   }