Add calls to EnsureGPUMemoryAvailable into GLES2DecoderImpl

gpu/command_buffer/service/memory_tracking.h

 // 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.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_MEMORY_TRACKING_H_
 #define GPU_COMMAND_BUFFER_SERVICE_MEMORY_TRACKING_H_
 
 #include <string>
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
 
 namespace gpu {
 namespace gles2 {
 
 // A MemoryTracker is used to propagate per-ContextGroup memory usage
 // statistics to the global GpuMemoryManager.
 class MemoryTracker : public base::RefCounted<MemoryTracker> {
  public:
    enum Pool {
      kUnmanaged,
      kManaged
    };
 
    virtual void TrackMemoryAllocatedChange(size_t old_size,
                                            size_t new_size,
                                            Pool pool) = 0;
 
+   // Ensure a certain amount of GPU memory is free. Returns true on success.
+   virtual bool EnsureGPUMemoryAvailable(size_t size_needed) = 0;
+
  protected:
   friend class base::RefCounted<MemoryTracker>;
   MemoryTracker() {}
   virtual ~MemoryTracker() {};
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MemoryTracker);
 };
 
 // A MemoryTypeTracker tracks the use of a particular type of memory (buffer,
@@ skipping 52 matching lines @@
   size_t mem_represented_;
   size_t mem_represented_at_last_update_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryTypeTracker);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_MEMORY_TRACKING_H_