https://bugs.webkit.org/show_bug.cgi?id=113094

        Reviewed by Darin Adler.

        Mac platform implementation has checks for pasteboard change count, but it
        didn't use to update the count when writing to pasteboad from JavaScript.

        * platform/PasteboardStrategy.h: Changed changeCount function to return a long
        instead of an int, as the underlying Mac type is NSInteger. Changed all methods
        that modify the pasteboard to return a new change count.

        * platform/PlatformPasteboard.h: Changed all methods that modify the pasteboard
        to return a new change count.

        * platform/mac/PasteboardMac.mm:
        (WebCore::Pasteboard::clear): Update m_changeCount.
        (WebCore::Pasteboard::writeSelectionForTypes): Ditto.
        (WebCore::Pasteboard::writePlainText): Ditto.
        (WebCore::writeURLForTypes): Ditto.
        (WebCore::Pasteboard::writeURL): Ditto.
        (WebCore::writeFileWrapperAsRTFDAttachment): Ditto.
        (WebCore::Pasteboard::writeImage): Ditto.
        (WebCore::Pasteboard::writePasteboard): Ditto.
        (WebCore::addHTMLClipboardTypesForCocoaType): Ditto.
        (WebCore::Pasteboard::writeString): Ditto.

        * platform/mac/PlatformPasteboardMac.mm:
        (WebCore::PlatformPasteboard::changeCount): Changed returned type to long to avoid
        data loss.
        (WebCore::PlatformPasteboard::copy): Return new change count.
        (WebCore::PlatformPasteboard::addTypes): Ditto.
        (WebCore::PlatformPasteboard::setTypes): Ditto.
        (WebCore::PlatformPasteboard::setBufferForType): Ditto.
        (WebCore::PlatformPasteboard::setPathnamesForType): Ditto.
        (WebCore::PlatformPasteboard::setStringForType): Ditto. Replaced -[NSURL writeToPasteboard:]
        with an equivalent implemnentation that tells use whether writing was successful.
        There is difference with invalid URL string handling - we used to silently ignore
        such requets, but set pasteboard content to empty URL now.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154639 268f45cc-cd09-0410-ab3c-d52691b4dbfc