Change ppapi C++ comment style into C.

ppapi/c/dev/ppp_class_deprecated.h

-// 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_PPP_CLASS_DEPRECATED_H_
 #define PPAPI_C_PPP_CLASS_DEPRECATED_H_
 
 #include "ppapi/c/dev/deprecated_bool.h"
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/c/pp_var.h"
 
 /**
  * @file
  * Defines the PPP_Class_Deprecated struct.
@@ skipping 109 matching lines @@
    * Called when the reference count of the object reaches 0. Normally, plugins
    * would free their internal data pointed to by the |object| pointer.
    */
   void (*Deallocate)(void* object);
 };
 
 /**
  * @}
  * End addtogroup PPP
  */
-#endif  // PPAPI_C_PPP_CLASS_DEPRECATED_H_
+#endif  /* PPAPI_C_PPP_CLASS_DEPRECATED_H_ */
+