ui: Cleanup class/struct forward declarations

services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h

Index: services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h
diff --git a/services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h b/services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h
index a390ff61a15a04ac62179b7fba4e72424cb6bfb0..2ec9e23076498f09891728768a5af25fb04d4b1f 100644
--- a/services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h
+++ b/services/ui/public/cpp/mojo_gpu_memory_buffer_manager.h
@@ -6,8 +6,10 @@
 #define SERVICES_UI_PUBLIC_CPP_MOJO_GPU_MEMORY_BUFFER_MANAGER_H_
 
 #include <memory>
+#include <vector>
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 #include "gpu/command_buffer/client/gpu_memory_buffer_manager.h"
 
 namespace ui {
@@ -17,6 +19,10 @@ class MojoGpuMemoryBufferManager : public gpu::GpuMemoryBufferManager {
   MojoGpuMemoryBufferManager();
   ~MojoGpuMemoryBufferManager() override;
 
+ private:
+  void DeletedGpuMemoryBuffer(gfx::GpuMemoryBufferId id,
+                              const gpu::SyncToken& sync_token);
+
   // Overridden from gpu::GpuMemoryBufferManager:
   std::unique_ptr<gfx::GpuMemoryBuffer> AllocateGpuMemoryBuffer(
       const gfx::Size& size,
@@ -32,7 +38,9 @@ class MojoGpuMemoryBufferManager : public gpu::GpuMemoryBufferManager {
   void SetDestructionSyncToken(gfx::GpuMemoryBuffer* buffer,
                                const gpu::SyncToken& sync_token) override;
 
- private:
+  int counter_ = 0;
+  base::WeakPtrFactory<MojoGpuMemoryBufferManager> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(MojoGpuMemoryBufferManager);
 };