Reviewed by Oliver.

    Reviewed by Oliver.

        Moved some constants from EventHandlerMac.mm to EventHandler.cpp
        Added some platform-specific data members and functions.

        * page/EventHandler.cpp:
        * page/EventHandler.h:
        * page/mac/EventHandlerMac.mm:
        * platform/PlatformMouseEvent.h:
        (WebCore::):
        (WebCore::PlatformMouseEvent::timestamp):
        (WebCore::PlatformMouseEvent::activatedWebView):
        (WebCore::PlatformMouseEvent::type):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@18007 268f45cc-cd09-0410-ab3c-d52691b4dbfc