Fix an uninitialized memory error reported by valgrind....

webkit/api/public/WebInputEvent.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 154 matching lines @@
         WebUChar unmodifiedText[textLengthCap];
 
         // This is a string identifying the key pressed.
         char keyIdentifier[keyIdentifierLengthCap];
 
         // This identifies whether this event was tagged by the system as being
         // a "system key" event (see
         // http://msdn.microsoft.com/en-us/library/ms646286(VS.85).aspx for
         // details).  Other platforms don't have this concept, but it's just
         // easier to leave it always false than ifdef.
-        bool isSystemKey;
+        // int is used instead of bool to ensure the size of this structure is
+        // strictly aligned to a factor of 4 bytes, otherwise memory check tools
+        // like valgrind may complain about uninitialized memory usage when
+        // transfering it over the wire.
+        int isSystemKey;
 
         WebKeyboardEvent(unsigned sizeParam = sizeof(WebKeyboardEvent))
             : WebInputEvent(sizeParam)
             , windowsKeyCode(0)
             , nativeKeyCode(0)
             , isSystemKey(false)
         {
             memset(&text, 0, sizeof(text));
             memset(&unmodifiedText, 0, sizeof(unmodifiedText));
             memset(&keyIdentifier, 0, sizeof(keyIdentifier));
@@ skipping 40 matching lines @@
     };
 
     // WebMouseWheelEvent ---------------------------------------------------------
 
     class WebMouseWheelEvent : public WebMouseEvent {
     public:
         float deltaX;
         float deltaY;
         float wheelTicksX;
         float wheelTicksY;
-        bool scrollByPage;
+
+        // int is used instead of bool to ensure the size of this structure is
+        // strictly aligned to a factor of 4 bytes, otherwise memory check tools
+        // like valgrind may complain about uninitialized memory usage when
+        // transfering it over the wire.
+        int scrollByPage;
 
         WebMouseWheelEvent(unsigned sizeParam = sizeof(WebMouseWheelEvent))
             : WebMouseEvent(sizeParam)
             , deltaX(0.0f)
             , deltaY(0.0f)
             , wheelTicksX(0.0f)
             , wheelTicksY(0.0f)
             , scrollByPage(false)
         {
         }
     };
 
 } // namespace WebKit
 
 #endif