Add initial GpuMemoryBufferSurfaceTexture implementation.

ui/gfx/gpu_memory_buffer.h

Index: ui/gfx/gpu_memory_buffer.h
diff --git a/ui/gfx/gpu_memory_buffer.h b/ui/gfx/gpu_memory_buffer.h
index 3510a911c0493ca3c4781120a3abd0976f78781f..3abd237c9296ac69cf6c532925d8ee583ed5528a 100644
--- a/ui/gfx/gpu_memory_buffer.h
+++ b/ui/gfx/gpu_memory_buffer.h
@@ -20,7 +20,8 @@ enum GpuMemoryBufferType {
   SHARED_MEMORY_BUFFER,
   EGL_CLIENT_BUFFER,
   IO_SURFACE_BUFFER,
-  GPU_MEMORY_BUFFER_TYPE_LAST = IO_SURFACE_BUFFER
+  SURFACE_TEXTURE_BUFFER,
+  GPU_MEMORY_BUFFER_TYPE_LAST = SURFACE_TEXTURE_BUFFER
 };
 
 struct GpuMemoryBufferHandle {
@@ -33,6 +34,9 @@ struct GpuMemoryBufferHandle {
 #if defined(OS_MACOSX)
         , io_surface_id(0)
 #endif
+#if defined(OS_ANDROID)
+        , surface_texture_id(0)
+#endif
   {
   }
   bool is_null() const { return type == EMPTY_BUFFER; }
@@ -44,7 +48,9 @@ struct GpuMemoryBufferHandle {
 #if defined(OS_MACOSX)
   uint32 io_surface_id;
 #endif
-
+#if defined(OS_ANDROID)
+  int32 surface_texture_id;
+#endif
 };
 
 // Interface for creating and accessing a zero-copy GPU memory buffer.