cc: Fix resource provider fences and add DCHECKs.

cc/gl_renderer.h

 // Copyright 2010 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_GL_RENDERER_H_
 #define CC_GL_RENDERER_H_
 
 #include "cc/cc_export.h"
 #include "cc/checkerboard_draw_quad.h"
 #include "cc/debug_border_draw_quad.h"
@@ skipping 213 matching lines @@
     bool m_discardBackbufferWhenNotVisible;
     bool m_isUsingBindUniform;
     bool m_visible;
     bool m_isScissorEnabled;
     bool m_blendShadow;
     unsigned m_programShadow;
     TexturedQuadDrawCache m_drawCache;
 
     scoped_ptr<ResourceProvider::ScopedWriteLockGL> m_currentFramebufferLock;
 
+    scoped_refptr<ResourceProvider::Fence> m_lastSwapFence;
+
     DISALLOW_COPY_AND_ASSIGN(GLRenderer);
 };
 
 
 // Setting DEBUG_GL_CALLS to 1 will call glGetError() after almost every GL
 // call made by the compositor. Useful for debugging rendering issues but
 // will significantly degrade performance.
 #define DEBUG_GL_CALLS 0
 
 #if DEBUG_GL_CALLS && !defined(NDEBUG)
 #define GLC(context, x) (x, GLRenderer::debugGLCall(&*context, #x, __FILE__, __LINE__))
 #else
 #define GLC(context, x) (x)
 #endif
 
 
 }
 
 #endif  // CC_GL_RENDERER_H_