Make PopupMenuTest wait for RenderWidgetHostView initialization

content/browser/site_per_process_browsertest.cc

 // Copyright (c) 2012 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 "content/browser/site_per_process_browsertest.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 6457 matching lines @@
   RenderWidgetHostInputEventRouter* router =
       static_cast<WebContentsImpl*>(shell()->web_contents())
           ->GetInputEventRouter();
   // Re-open the select element.
   click_event.SetPositionInWidget(360, 90);
   click_event.click_count = 1;
   router->RouteMouseEvent(rwhv_root, &click_event, ui::LatencyInfo());
 
   filter->Wait();
 
-  RenderWidgetHostView* popup_view =
+  RenderWidgetHostViewAura* popup_view = static_cast<RenderWidgetHostViewAura*>(
       RenderWidgetHost::FromID(process_id, filter->last_routing_id())
-          ->GetView();
+          ->GetView());
+  // The IO thread posts to ViewMsg_ShowWidget handlers in both the message
+  // filter above and the WebContents, which initializes the popup's view.
+  // It is possible for this code to execute before the WebContents handler,
+  // in which case OnMouseEvent would be called on an uninitialized RWHVA.
+  // This loop ensures that the initialization completes before proceeding.
+  while (!popup_view->window()) {
+    base::RunLoop loop;
+    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                  loop.QuitClosure());
+    loop.Run();
+  }
 
   RenderWidgetHostMouseEventMonitor popup_monitor(
       popup_view->GetRenderWidgetHost());
 
   // Next send a mouse up directly targeting the first option, simulating a
   // drag. This requires a ui::MouseEvent because it tests behavior that is
   // above RWH input event routing.
   ui::MouseEvent mouse_up_event(ui::ET_MOUSE_RELEASED, gfx::Point(10, 5),
                                 gfx::Point(10, 5), ui::EventTimeForNow(),
                                 ui::EF_LEFT_MOUSE_BUTTON,
                                 ui::EF_LEFT_MOUSE_BUTTON);
-  static_cast<RenderWidgetHostViewAura*>(popup_view)
-      ->OnMouseEvent(&mouse_up_event);
+  popup_view->OnMouseEvent(&mouse_up_event);
 
   // This verifies that the popup actually received the event, and it wasn't
   // diverted to a different RenderWidgetHostView due to mouse capture.
   EXPECT_TRUE(popup_monitor.EventWasReceived());
 #endif
 }
 
 // Test that clicking a select element in a nested out-of-process iframe creates
 // a popup menu in the correct position, even if the top-level page repositions
 // its out-of-process iframe. This verifies that screen positioning information
@@ skipping 3677 matching lines @@
   // Go back again.  This should go to foo.com.
   {
     TestNavigationObserver back_observer(web_contents());
     web_contents()->GetController().GoBack();
     back_observer.Wait();
   }
   EXPECT_EQ(foo_url, web_contents()->GetMainFrame()->GetLastCommittedURL());
 }
 
 }  // namespace content