Add GetUsbKeyCode dev interface for Pepper key events

ppapi/shared_impl/ppb_input_event_shared.h

Index: ppapi/shared_impl/ppb_input_event_shared.h
diff --git a/ppapi/shared_impl/ppb_input_event_shared.h b/ppapi/shared_impl/ppb_input_event_shared.h
index c9ab572f0dcf76b267791320e96c9811f3178f40..c62befae60a954b7708dc6c1137703028d3c87ad 100644
--- a/ppapi/shared_impl/ppb_input_event_shared.h
+++ b/ppapi/shared_impl/ppb_input_event_shared.h
@@ -40,6 +40,7 @@ struct PPAPI_SHARED_EXPORT InputEventData {
   bool wheel_scroll_by_page;
 
   uint32_t key_code;
+  uint32_t usb_key_code;
 
   std::string character_text;
 
@@ -76,6 +77,8 @@ class PPAPI_SHARED_EXPORT PPB_InputEvent_Shared
   virtual PP_Bool GetWheelScrollByPage() OVERRIDE;
   virtual uint32_t GetKeyCode() OVERRIDE;
   virtual PP_Var GetCharacterText() OVERRIDE;
+  virtual PP_Bool SetUsbKeyCode(uint32_t usb_key_code) OVERRIDE;
+  virtual uint32_t GetUsbKeyCode() OVERRIDE;
   virtual uint32_t GetIMESegmentNumber() OVERRIDE;
   virtual uint32_t GetIMESegmentOffset(uint32_t index) OVERRIDE;
   virtual int32_t GetIMETargetSegment() OVERRIDE;