Change mojo geometry structs from using type converters to StructTraits.

components/mus/gpu/gpu_service_mus.h

Index: components/mus/gpu/gpu_service_mus.h
diff --git a/components/mus/gpu/gpu_service_mus.h b/components/mus/gpu/gpu_service_mus.h
index a8d5696ea3c4065ef1a5596e3a45acf106f7e319..0dcd4efb4366f91a556b8a01b11ec0a1106a624a 100644
--- a/components/mus/gpu/gpu_service_mus.h
+++ b/components/mus/gpu/gpu_service_mus.h
@@ -30,7 +30,7 @@ class GpuServiceMus : public mojom::GpuService,
 
   void CreateGpuMemoryBuffer(
       mojom::GpuMemoryBufferIdPtr id,
-      mojo::SizePtr size,
+      const gfx::Size& size,
       mojom::BufferFormat format,
       mojom::BufferUsage usage,
       uint64_t surface_id,
@@ -40,7 +40,7 @@ class GpuServiceMus : public mojom::GpuService,
   void CreateGpuMemoryBufferFromHandle(
       mojom::GpuMemoryBufferHandlePtr buffer_handle,
       mojom::GpuMemoryBufferIdPtr id,
-      mojo::SizePtr size,
+      const gfx::Size& size,
       mojom::BufferFormat format,
       const mojom::GpuService::CreateGpuMemoryBufferFromHandleCallback&
           callback) override;