cc: Make RenderPass into a struct-like class.

cc/quad_culler.h

 // Copyright 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.
 
 #ifndef CC_QUAD_CULLER_H_
 #define CC_QUAD_CULLER_H_
 
 #include "cc/cc_export.h"
 #include "cc/quad_sink.h"
 #include "cc/render_pass.h"
 
 namespace cc {
 class LayerImpl;
 class RenderSurfaceImpl;
 template<typename LayerType, typename SurfaceType>
 class OcclusionTrackerBase;
 
 class CC_EXPORT QuadCuller : public QuadSink {
 public:
-    QuadCuller(QuadList&, SharedQuadStateList&, const LayerImpl*, const OcclusionTrackerBase<LayerImpl, RenderSurfaceImpl>*, bool showCullingWithDebugBorderQuads, bool forSurface);
+    QuadCuller(QuadList&, SharedQuadStateList&, const LayerImpl*, const OcclusionTrackerBase<LayerImpl, RenderSurfaceImpl>&, bool showCullingWithDebugBorderQuads, bool forSurface);
     virtual ~QuadCuller() { }
 
     // QuadSink implementation.
     virtual SharedQuadState* useSharedQuadState(scoped_ptr<SharedQuadState>) OVERRIDE;
     virtual bool append(scoped_ptr<DrawQuad>, AppendQuadsData&) OVERRIDE;
 
 private:
     QuadList& m_quadList;
     SharedQuadStateList& m_sharedQuadStateList;
+    const LayerImpl* m_layer;
+    const OcclusionTrackerBase<LayerImpl, RenderSurfaceImpl>& m_occlusionTracker;
+
     SharedQuadState* m_currentSharedQuadState;
-    const LayerImpl* m_layer;
-    const OcclusionTrackerBase<LayerImpl, RenderSurfaceImpl>* m_occlusionTracker;
     bool m_showCullingWithDebugBorderQuads;
     bool m_forSurface;
 };
 
 }
 #endif  // CC_QUAD_CULLER_H_