cc: Rename TileTaskClient interface to RasterBufferProvider.

cc/raster/raster_buffer.h

Index: cc/raster/raster_buffer.h
diff --git a/cc/raster/raster_buffer.h b/cc/raster/raster_buffer.h
index 04972f9d73e11117f81753977b4289ef260c3997..54c5b9ebe7ac9fc57e0609e6c9d2b4a915ce98c5 100644
--- a/cc/raster/raster_buffer.h
+++ b/cc/raster/raster_buffer.h
@@ -12,6 +12,20 @@
 #include "ui/gfx/geometry/rect.h"
 
 namespace cc {
+class RasterBuffer;
+class Resource;
+
+class CC_EXPORT RasterBufferProvider {
+ public:
+  virtual std::unique_ptr<RasterBuffer> AcquireBufferForRaster(
+      const Resource* resource,
+      uint64_t resource_content_id,
+      uint64_t previous_content_id) = 0;
+  virtual void ReleaseBufferForRaster(std::unique_ptr<RasterBuffer> buffer) = 0;
+
+ protected:
+  virtual ~RasterBufferProvider() {}
+};
 
 class CC_EXPORT RasterBuffer {
  public: