Changeset 125733 in webkit

Timestamp:

Aug 15, 2012, 6:27:41 PM (14 years ago)

Author:

tkent@chromium.org

Message:

Merge 123637 - ​https://bugs.webkit.org/show_bug.cgi?id=89114
REGRESSION (r112919): Setting scrollTop after setting display from none to block
fails
-and corresponding-
<rdar://problem/11656050>

Reviewed by Simon Fraser.

Source/WebCore:

ScrollAnimatorMac::immediateScrollTo() and ScrollAnimatorMac::immediateScrollBy()
both have an optimization in place so that they do not call
notifyPositionChanged() if the new scroll offset matches the ScrollAnimator's
cached m_currentPosX and m_currentPosY. So revision 112919 caused troubled with
this optimization because it allowed RenderLayers to restore a scrollOffset from
the Element if there is one cached there. This caused the RenderLayer to have a
scrollOffset that is improperly out-of-synch with the ScrollAnimator's
currentPosition (which will just be 0,0 since it is being re-created like the
RenderLayer). This fix makes sure they are in synch by calling
setCurrentPosition() on the ScrollAnimator when the cached position is non-zero.

• rendering/RenderLayer.cpp:

(WebCore::RenderLayer::RenderLayer):

LayoutTests:

• fast/overflow/setting-scrollTop-after-hide-show-expected.txt: Added.
• fast/overflow/setting-scrollTop-after-hide-show.html: Added.

TBR=​karen@chromium.org
Review URL: ​https://chromiumcodereview.appspot.com/10823356

Location:

branches/chromium/1180

Files:

• LayoutTests/fast/overflow/setting-scrollTop-after-hide-show-expected.txt (copied) (copied from trunk/LayoutTests/fast/overflow/setting-scrollTop-after-hide-show-expected.txt )
• LayoutTests/fast/overflow/setting-scrollTop-after-hide-show.html (copied) (copied from trunk/LayoutTests/fast/overflow/setting-scrollTop-after-hide-show.html )
• Source/WebCore/rendering/RenderLayer.cpp (modified) (2 diffs)

branches/chromium/1180/Source/WebCore/rendering/RenderLayer.cpp

@@ -87 +87 @@
 #include "RenderView.h"
 #include "ScaleTransformOperation.h"
+#include "ScrollAnimator.h"
 #include "Scrollbar.h"
 #include "ScrollbarTheme.h"
@@ -191 +192 @@
         Element* element = toElement(node);
         m_scrollOffset = element->savedLayerScrollOffset();
+        if (!m_scrollOffset.isZero())
+            scrollAnimator()->setCurrentPosition(FloatPoint(m_scrollOffset.width(), m_scrollOffset.height()));
         element->setSavedLayerScrollOffset(IntSize());
     }