Change ppapi C++ comment style into C.

ppapi/c/dev/ppb_var_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_PPB_VAR_DEPRECATED_H_
 #define PPAPI_C_PPB_VAR_DEPRECATED_H_
 
 #include "ppapi/c/dev/deprecated_bool.h"
 #include "ppapi/c/pp_module.h"
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/c/pp_var.h"
 
 struct PPP_Class_Deprecated;
 
@@ skipping 218 matching lines @@
    */
   struct PP_Var (*CreateObject)(PP_Module module,
                                 const struct PPP_Class_Deprecated* object_class,
                                 void* object_data);
 };
 
 /**
  * @}
  * End addtogroup PPB
  */
-#endif  // PPAPI_C_PPB_VAR_DEPRECATED_H_
+#endif  /* PPAPI_C_PPB_VAR_DEPRECATED_H_ */
+