cc: Free gpu resources when we are invisible or TM is oom.

cc/resources/gpu_rasterizer.h

Index: cc/resources/gpu_rasterizer.h
diff --git a/cc/resources/gpu_rasterizer.h b/cc/resources/gpu_rasterizer.h
index 8c75f326d0d22ffd5e1b7cf8e5b686ec613d854d..2d602285226379a831cb99746d9fd39545664f5f 100644
--- a/cc/resources/gpu_rasterizer.h
+++ b/cc/resources/gpu_rasterizer.h
@@ -44,6 +44,8 @@ class CC_EXPORT GpuRasterizer : public Rasterizer {
                        float scale);
 
   ResourceProvider* resource_provider() { return resource_provider_; }
+  void ClearCache();
+  void RestoreCacheLimits();
 
  private:
   GpuRasterizer(ContextProvider* context_provider,
@@ -68,6 +70,9 @@ class CC_EXPORT GpuRasterizer : public Rasterizer {
   bool use_distance_field_text_;
   bool threaded_gpu_rasterization_enabled_;
   int msaa_sample_count_;
+  int maxTextures_;
+  size_t maxTextureBytes_;
+  bool cache_cleared_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuRasterizer);
 };