Convert MouseEvents from DIPS to Pixels before passing it to surfaces for hittesting.

content/browser/renderer_host/render_widget_host_view_aura.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/renderer_host/render_widget_host_view_aura.h"
 
 #include <set>
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
@@ skipping 2149 matching lines @@
     window_->parent()->delegate()->OnMouseEvent(event);
   }
 
   if (!IsXButtonUpEvent(event))
     event->SetHandled();
 }
 
 uint32_t RenderWidgetHostViewAura::SurfaceIdNamespaceAtPoint(
     const gfx::Point& point,
     gfx::Point* transformed_point) {
-  cc::SurfaceId id =
-      delegated_frame_host_->SurfaceIdAtPoint(point, transformed_point);
+  aura::WindowTreeHost* host = window_->GetHost();
+  gfx::Point point_in_pixels(point);
+  host->GetRootTransform().TransformPoint(&point_in_pixels);

[sadrul, 2015/09/11 17:48:10]

Does this do the right thing when the display is rotated on a chromeos device?
Because the root-transform possibly includes the rotation transforms that you
don't want to use?

Also, can you add tests?

+  cc::SurfaceId id = delegated_frame_host_->SurfaceIdAtPoint(point_in_pixels,
+                                                             transformed_point);
+  host->GetInverseRootTransform().TransformPoint(transformed_point);
+
   // It is possible that the renderer has not yet produced a surface, in which
   // case we return our current namespace.
   if (id.is_null())
     return GetSurfaceIdNamespace();
   return cc::SurfaceIdAllocator::NamespaceForId(id);
 }
 
 void RenderWidgetHostViewAura::ProcessMouseEvent(
     const blink::WebMouseEvent& event) {
   host_->ForwardMouseEvent(event);
@@ skipping 700 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewBase, public:
 
 // static
 void RenderWidgetHostViewBase::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content