linux_aura: Improve window drag performance.

content/browser/web_contents/web_contents_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/web_contents/web_contents_view_aura.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 680 matching lines @@
   }
 
   virtual void OnWindowRemovingFromRootWindow(aura::Window* window) OVERRIDE {
     if (window != parent_)
       window->GetDispatcher()->RemoveRootWindowObserver(this);
   }
 
   // Overridden RootWindowObserver:
   virtual void OnRootWindowHostMoved(const aura::RootWindow* root,
                                      const gfx::Point& new_origin) OVERRIDE {
+    TRACE_EVENT1("ui",
+                 "WebContentsViewAura::WindowObserver::OnRootWindowHostMoved",
+                 "new_origin", new_origin.ToString());
+
     // This is for the desktop case (i.e. Aura desktop).
     SendScreenRects();
   }
 
  private:
   void SendScreenRects() {
     RenderWidgetHostImpl::From(view_->web_contents_->GetRenderViewHost())->
         SendScreenRects();
   }
 
@@ skipping 935 matching lines @@
       event.location(),
       gfx::Screen::GetScreenFor(GetNativeView())->GetCursorScreenPoint(),
       ConvertAuraEventFlagsToWebInputEventModifiers(event.flags()));
   if (drag_dest_delegate_)
     drag_dest_delegate_->OnDrop();
   current_drop_data_.reset();
   return current_drag_op_;
 }
 
 }  // namespace content