Reviewed by Mihai Parparita.

        Chromium Mac: Enable overlay scrollbars
        https://bugs.webkit.org/show_bug.cgi?id=59756

        Enable WTF_USE_WK_SCROLLBAR_PAINTER for Chromium Mac. This allows us to use overlay scrollbars on future versions of Mac OS X.

        * wtf/Platform.h:
2011-06-08  Sailesh Agrawal  <sail@chromium.org>

        Reviewed by Mihai Parparita.

        Chromium Mac: Enable overlay scrollbars
        https://bugs.webkit.org/show_bug.cgi?id=59756

        Sync ScrollbarThemeChromiumMac.mm/.h with ScrollbarThemeMac.mm to pick up support for overlay scrollbars. The only changes are renaming ScrollbarThemeMac to ScrollbarThemeChromiumMac and using runtime checks instead of #ifdef's.

        No new tests, since this code is only enabled on future versions of Mac OS X.

        * platform/chromium/ScrollAnimatorChromiumMac.mm: All changes to this file except in scroll() were to swap #if USE(WK_SCROLLBAR_PAINTER) with runtime checks.
        (WebCore::ScrollAnimatorChromiumMac::ScrollAnimatorChromiumMac):
        (WebCore::ScrollAnimatorChromiumMac::~ScrollAnimatorChromiumMac):
        (WebCore::ScrollAnimatorChromiumMac::notityPositionChanged):
        (WebCore::ScrollAnimatorChromiumMac::contentAreaWillPaint):
        (WebCore::ScrollAnimatorChromiumMac::mouseEnteredContentArea):
        (WebCore::ScrollAnimatorChromiumMac::mouseExitedContentArea):
        (WebCore::ScrollAnimatorChromiumMac::mouseMovedInContentArea):
        (WebCore::ScrollAnimatorChromiumMac::willStartLiveResize):
        (WebCore::ScrollAnimatorChromiumMac::contentsResized):
        (WebCore::ScrollAnimatorChromiumMac::willEndLiveResize):
        (WebCore::ScrollAnimatorChromiumMac::contentAreaDidShow):
        (WebCore::ScrollAnimatorChromiumMac::contentAreaDidHide):
        (WebCore::ScrollAnimatorChromiumMac::didBeginScrollGesture):
        (WebCore::ScrollAnimatorChromiumMac::didEndScrollGesture):
        (WebCore::ScrollAnimatorChromiumMac::didAddVerticalScrollbar):
        (WebCore::ScrollAnimatorChromiumMac::willRemoveVerticalScrollbar):
        (WebCore::ScrollAnimatorChromiumMac::didAddHorizontalScrollbar):
        (WebCore::ScrollAnimatorChromiumMac::willRemoveHorizontalScrollbar):
        (WebCore::ScrollAnimatorChromiumMac::cancelAnimations):
        * platform/chromium/ScrollbarOverlayUtilitiesChromiumMac.mm:
        (preferredScrollerStyle): Disabled overlay scrollbar styles due to trailing artifacts.
        (wkScrollbarPainterPaint): Fixed a problem where the scrollbar track wasn't being drawn.
        (wkScrollbarPainterKnobRect): Implemented a previously unimplemented function.
        (wkSetScrollbarPainterKnobStyle): Implemented a function that's now supported by the latest Mac OS X seeds.
        (isScrollbarOverlayAPIAvailable): Enabled new scrollbar code.
        * platform/chromium/ScrollbarThemeChromiumMac.h:
        * platform/chromium/ScrollbarThemeChromiumMac.mm: Sync with ScrollbarThemeMac.mm.
        (WebCore::scrollbarMap):
        (+[ScrollbarPrefsObserver appearancePrefsChanged:]):
        (WebCore::updateArrowPlacement):
        (WebCore::ScrollbarThemeChromiumMac::registerScrollbar):
        (WebCore::ScrollbarThemeChromiumMac::unregisterScrollbar):
        (WebCore::ScrollbarThemeChromiumMac::setNewPainterForScrollbar):
        (WebCore::ScrollbarThemeChromiumMac::painterForScrollbar):
        (WebCore::ScrollbarThemeChromiumMac::scrollbarThickness):
        (WebCore::ScrollbarThemeChromiumMac::usesOverlayScrollbars):
        (WebCore::ScrollbarThemeChromiumMac::hasButtons):
        (WebCore::ScrollbarThemeChromiumMac::hasThumb):
        (WebCore::buttonRepaintRect):
        (WebCore::ScrollbarThemeChromiumMac::minimumThumbLength):
        (WebCore::ScrollbarThemeChromiumMac::shouldDragDocumentInsteadOfThumb):
        (WebCore::toScrollbarPainterKnobStyle):
        (WebCore::ScrollbarThemeChromiumMac::paint):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@88396 268f45cc-cd09-0410-ab3c-d52691b4dbfc