linux_aura: Improve window drag performance.

chrome/browser/ui/aura/tabs/dock_info_auralinux.cc

 // Copyright 2013 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 "chrome/browser/ui/tabs/dock_info.h"
 
+#include "base/debug/trace_event.h"
 #include "chrome/browser/ui/host_desktop.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #if defined(USE_X11)
 #include "ui/base/x/x11_util.h"
 #endif
 
 #if !defined(OS_CHROMEOS) && defined(USE_X11)
 #include "ui/views/widget/desktop_aura/desktop_root_window_host_x11.h"
 
@@ skipping 155 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(LocalProcessWindowFinder);
 };
 
 }  // namespace
 
 // static
 gfx::NativeView DockInfo::GetLocalProcessWindowAtPoint(
     chrome::HostDesktopType host_desktop_type,
     const gfx::Point& screen_point,
     const std::set<gfx::NativeView>& ignore) {
+  TRACE_EVENT1("ui", "DockInfo::GetLocalProcessWindowAtPoint",
+               "screen_point", screen_point.ToString());
+
   // The X11 server is the canonical state of what the window stacking order
   // is.
   XID xid =
       LocalProcessWindowFinder::GetProcessWindowAtPoint(screen_point, ignore);
   return views::DesktopRootWindowHostX11::GetContentWindowForXID(xid);
 }
 #else
 // static
 gfx::NativeView DockInfo::GetLocalProcessWindowAtPoint(
     chrome::HostDesktopType host_desktop_type,
@@ skipping 18 matching lines @@
 bool DockInfo::GetWindowBounds(gfx::Rect* bounds) const {
   if (!window())
     return false;
   *bounds = window_->bounds();
   return true;
 }
 
 void DockInfo::SizeOtherWindowTo(const gfx::Rect& bounds) const {
   window_->SetBounds(bounds);
 }