linux_aura: Improve window drag performance.

ui/aura/root_window.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 "ui/aura/root_window.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 885 matching lines @@
 void RootWindow::OnHostLostMouseGrab() {
   mouse_pressed_handler_ = NULL;
   mouse_moved_handler_ = NULL;
 }
 
 void RootWindow::OnHostPaint(const gfx::Rect& damage_rect) {
   compositor_->ScheduleRedrawRect(damage_rect);
 }
 
 void RootWindow::OnHostMoved(const gfx::Point& origin) {
+  TRACE_EVENT1("ui", "RootWindow::OnHostMoved",
+               "origin", origin.ToString());
+
   FOR_EACH_OBSERVER(RootWindowObserver, observers_,
                     OnRootWindowHostMoved(this, origin));
 }
 
 void RootWindow::OnHostResized(const gfx::Size& size) {
+  TRACE_EVENT1("ui", "RootWindow::OnHostResized",
+               "size", size.ToString());
+
   DispatchHeldEvents();
   // The compositor should have the same size as the native root window host.
   // Get the latest scale from display because it might have been changed.
   compositor_->SetScaleAndSize(GetDeviceScaleFactorFromDisplay(this), size);
 
   // The layer, and the observers should be notified of the
   // transformed size of the root window.
   UpdateRootWindowSize(size);
   FOR_EACH_OBSERVER(RootWindowObserver, observers_,
                     OnRootWindowHostResized(this));
@@ skipping 243 matching lines @@
 }
 
 gfx::Transform RootWindow::GetInverseRootTransform() const {
   float scale = ui::GetDeviceScaleFactor(layer());
   gfx::Transform transform;
   transform.Scale(1.0f / scale, 1.0f / scale);
   return transformer_->GetInverseTransform() * transform;
 }
 
 }  // namespace aura