[Device Service] Move Gamepad Blink headers to be part of the Gamepad client library

third_party/WebKit/public/platform/Platform.h

Index: third_party/WebKit/public/platform/Platform.h
diff --git a/third_party/WebKit/public/platform/Platform.h b/third_party/WebKit/public/platform/Platform.h
index eab1ca5647cb791538ec8b33fef4eaba3584bd08..28b05e6dae485248cfff9941cec2e3e815afb239 100644
--- a/third_party/WebKit/public/platform/Platform.h
+++ b/third_party/WebKit/public/platform/Platform.h
@@ -43,7 +43,6 @@
 #include "WebDeviceLightListener.h"
 #include "WebFeaturePolicy.h"
 #include "WebGamepadListener.h"
-#include "WebGamepads.h"
 #include "WebGestureDevice.h"
 #include "WebLocalizedString.h"
 #include "WebMessagePortChannel.h"
@@ -60,6 +59,10 @@
 #include "cc/surfaces/frame_sink_id.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 
+namespace device {
+class Gamepads;
+}
+
 namespace gpu {
 class GpuMemoryBufferManager;
 }
@@ -280,7 +283,7 @@ class BLINK_PLATFORM_EXPORT Platform {
 
   // Gamepad -------------------------------------------------------------
 
-  virtual void SampleGamepads(WebGamepads& into) {}
+  virtual void SampleGamepads(device::Gamepads& into) {}
 
   // History -------------------------------------------------------------