linux_aura: Improve window drag performance.

ui/aura/root_window.cc

Index: ui/aura/root_window.cc
diff --git a/ui/aura/root_window.cc b/ui/aura/root_window.cc
index 53b8829208d428a892b3d2038a874fd678a63c0b..775a6acd264b9c24c77f967f23a201f1be320000 100644
--- a/ui/aura/root_window.cc
+++ b/ui/aura/root_window.cc
@@ -903,11 +903,17 @@ void RootWindow::OnHostPaint(const gfx::Rect& 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.