Impl mus::mojom::GpuService to enable using Chrome IPC version gpu CmdBuf in mus

components/mus/public/cpp/window_manager_delegate.h

Index: components/mus/public/cpp/window_manager_delegate.h
diff --git a/components/mus/public/cpp/window_manager_delegate.h b/components/mus/public/cpp/window_manager_delegate.h
index 31af262c8883a9b9f52ab7040082c82ce0c4dc9d..c07bd30ff32f45159964316f8b15e6a0463e727d 100644
--- a/components/mus/public/cpp/window_manager_delegate.h
+++ b/components/mus/public/cpp/window_manager_delegate.h
@@ -13,6 +13,7 @@
 #include <vector>
 
 #include "base/callback_forward.h"
+#include "components/mus/public/cpp/mus_public_export.h"
 #include "components/mus/public/interfaces/cursor.mojom.h"
 #include "components/mus/public/interfaces/event_matcher.mojom.h"
 #include "components/mus/public/interfaces/input_events.mojom.h"
@@ -34,7 +35,7 @@ class Window;
 
 // See the mojom with the same name for details on the functions in this
 // interface.
-class WindowManagerClient {
+class MUS_PUBLIC_EXPORT WindowManagerClient {
  public:
   virtual void SetFrameDecorationValues(
       mojom::FrameDecorationValuesPtr values) = 0;