https://bugs.webkit.org/show_bug.cgi?id=107628
Sometimes scroll position is jerky during rubber-band, affects nytimes.com
-and corresponding-
<rdar://problem/12679549>
Reviewed by Simon Fraser.
The basic problem here is that isRubberBandInProgress() was only implemented for
main thread scrolling. So when we were actually scrolling on the scrolling thread,
that function would always return false regardless.
New ScrollableArea virtual function isRubberBandInProgress() will allow us to ask
the ScrollingCoordinator when the scrolling thread is scrolling, or the
ScrollAnimator otherwise.
* page/FrameView.cpp:
(WebCore::FrameView::isRubberBandInProgress):
* page/FrameView.h:
(FrameView):
* platform/ScrollableArea.h:
(WebCore::ScrollableArea::isRubberBandInProgress):
New ScrollingCoordinator function isRubberBandInProgress() always returns false
for non-Mac ports, and is overridden in ScrollingCoordinatorMac to consult the
ScrollingTree.
* page/scrolling/ScrollingCoordinator.h:
(WebCore::ScrollingCoordinator::isRubberBandInProgress):
* page/scrolling/mac/ScrollingCoordinatorMac.h:
(ScrollingCoordinatorMac):
* page/scrolling/mac/ScrollingCoordinatorMac.mm:
(WebCore::ScrollingCoordinatorMac::isRubberBandInProgress):
New variable m_mainFrameIsRubberBanding keeps track of whether there is currently
a rubber-band happening on the scrolling thread.
* page/scrolling/ScrollingTree.cpp:
(WebCore::ScrollingTree::ScrollingTree):
(WebCore::ScrollingTree::isRubberBandInProgress):
(WebCore::ScrollingTree::setMainFrameIsRubberBanding):
* page/scrolling/ScrollingTree.h:
(ScrollingTree):
(WebCore::ScrollingTree::rootNode):
Call setMainFrameIsRubberBanding() whenever the stretchAmount is calculated and
whenever we stop the rubber-band timer.
* page/scrolling/mac/ScrollingTreeScrollingNodeMac.mm:
(WebCore::ScrollingTreeScrollingNodeMac::stretchAmount):
(WebCore::ScrollingTreeScrollingNodeMac::stopSnapRubberbandTimer):
Consult FrameView for isRubberBandInProgress().
* platform/ScrollView.cpp:
(WebCore::ScrollView::updateScrollbars):
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140571 268f45cc-cd09-0410-ab3c-d52691b4dbfc
11 files changed
