Remove 'char' from IDL

ppapi/api/ppb_gamepad.idl

 /* Copyright (c) 2012 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.
  */
 
 /**
  * This file defines the <code>PPB_Gamepad</code> interface, which
  * provides access to gamepad devices.
  */
 
@@ skipping 41 matching lines @@
      */
     uint16_t[128] id;
 
     /**
      * Is there a gamepad connected at this index? If this is false, no other
      * data in this structure is valid.
      */
     PP_Bool connected;
 
     /* Padding to make the struct the same size between 64 and 32. */
-    char[4] unused_pad_;
+    int8_t[4] unused_pad_;
 };
 
 /**
  * The data for all gamepads connected to the system.
  */
 [assert_size(1896)]
 struct PP_GamepadsSampleData {
     /**
      * Number of valid elements in the |items| array.
      */
     uint32_t length;
 
     /* Padding to make the struct the same size between 64 and 32. */
-    char[4] unused_pad_;
+    int8_t[4] unused_pad_;
 
     /**
      * Data for an individual gamepad device connected to the system.
      */
     PP_GamepadSampleData[4] items;
 };
 
 /**
  * The <code>PPB_Gamepad</code> interface allows retrieving data from
  * gamepad/joystick devices that are connected to the system.
  */
 [version=1.0, macro="PPB_GAMEPAD_INTERFACE", singleton]
 interface PPB_Gamepad {
   /**
    * Samples the current state of the available gamepads.
    */
   [always_set_output_parameters]
   void Sample(
       [in] PP_Instance instance,
       [out] PP_GamepadsSampleData data);
 };