Change ppapi C++ comment style into C.

ppapi/c/dev/ppb_fullscreen_dev.h

Index: ppapi/c/dev/ppb_fullscreen_dev.h
diff --git a/ppapi/c/dev/ppb_fullscreen_dev.h b/ppapi/c/dev/ppb_fullscreen_dev.h
index 22b19dfcc56e7772180486d5d5567721fdaf1611..ebf2adef024078a1262ac4193aa58d094fdd8ccf 100644
--- a/ppapi/c/dev/ppb_fullscreen_dev.h
+++ b/ppapi/c/dev/ppb_fullscreen_dev.h
@@ -1,7 +1,7 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
+/* Copyright (c) 2010 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
 #ifndef PPAPI_C_DEV_PPB_FULLSCREEN_DEV_H_
 #define PPAPI_C_DEV_PPB_FULLSCREEN_DEV_H_
 
@@ -25,4 +25,5 @@ struct PPB_Fullscreen_Dev {
   PP_Bool (*SetFullscreen)(PP_Instance instance, PP_Bool fullscreen);
 };
 
-#endif  // PPAPI_C_DEV_PPB_FULLSCREEN_DEV_H_
+#endif  /* PPAPI_C_DEV_PPB_FULLSCREEN_DEV_H_ */
+