exo: Only create new SurfaceLayer if layer properties change.

components/exo/pointer.cc

 // Copyright 2015 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 "components/exo/pointer.h"
 
 #include "ash/common/shell_window_ids.h"
 #include "ash/display/display_info.h"
 #include "ash/display/display_manager.h"
 #include "ash/shell.h"
@@ skipping 220 matching lines @@
 }
 
 void Pointer::OnScrollEvent(ui::ScrollEvent* event) {
   OnMouseEvent(event);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // SurfaceDelegate overrides:
 
 void Pointer::OnSurfaceCommit() {
+  surface_->CheckForCommittingToNewSurface();
   surface_->CommitSurfaceHierarchy();
   surface_->SetBounds(gfx::Rect(gfx::Point() - hotspot_.OffsetFromOrigin(),
                                 surface_->layer()->size()));
 }
 
 bool Pointer::IsSurfaceSynchronized() const {
   // A pointer surface is always desynchronized.
   return false;
 }
 
@@ skipping 33 matching lines @@
 Surface* Pointer::GetEffectiveTargetForEvent(ui::Event* event) const {
   Surface* target =
       Surface::AsSurface(static_cast<aura::Window*>(event->target()));
   if (!target)
     return nullptr;
 
   return delegate_->CanAcceptPointerEventsForSurface(target) ? target : nullptr;
 }
 
 }  // namespace exo