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Content offset in this codepen when switching tabs
https://bugs.webkit.org/show_bug.cgi?id=231989

Reviewed by Tim Horton.

Source/WebCore:

There were two problems that occurred with async-scrollable iframes when their associated
WKWebView was removed and re-added to the view hierarchy (e.g. when switching tabs).
These resulted in misplaced position:fixed content, and the first user scroll in the
iframe causing the scroll position to jump back to the top.

The positon:fixed issue was caused by an ordering problem in
ScrollingTreeFrameScrollingNode::commitStateBeforeChildren() which resulted in the layout
viewport being computed incorrectly; we called updateViewportForCurrentScrollPosition()
before setting the min and max scroll position, so we'd always clamp the layout viewport to
a location of 0,0.

The second scroll position reset issue was caused by the ScrollingTreeScrollingNode's
m_currentScrollPosition reverting to a stale after re-attaching the iframe's scrolling
subtree. ScrollingTreeScrollingNode::commitStateBeforeChildren() has code to set
m_currentScrollPosition from the state tree node's scroll position on first commit;
the issue was that ScrollingStateScrollingNode's scrollPosition() was not updated on every
scroll, only when something triggered a scrolling tree commit.

Fix by silently updating ScrollingStateScrollingNode's scrollPosition() when we get
notifications back from the scrolling thread that a scroll happened.

Both fixes are tested by the ScrollingCoordinatorTests.ScrollingTreeAfterDetachReattach API test.

* page/scrolling/AsyncScrollingCoordinator.cpp:
(WebCore::AsyncScrollingCoordinator::updateScrollPositionAfterAsyncScroll):
* page/scrolling/ScrollingStateScrollingNode.cpp:
(WebCore::ScrollingStateScrollingNode::syncScrollPosition):
(WebCore::ScrollingStateScrollingNode::hasScrollPositionRequest const):
* page/scrolling/ScrollingStateScrollingNode.h:
* page/scrolling/ScrollingStateTree.cpp:
(WebCore::ScrollingStateTree::insertNode):
* page/scrolling/ScrollingTreeFrameScrollingNode.cpp:
(WebCore::ScrollingTreeFrameScrollingNode::commitStateBeforeChildren): We need to check
state.hasScrollPositionRequest(), otherwise the "cancel animated scroll request" that comes
out of Page::stopKeyboardScrollAnimation() prevents scroll position restoration.
* page/scrolling/ScrollingTreeScrollingNode.cpp:
(WebCore::ScrollingTreeScrollingNode::commitStateBeforeChildren):
(WebCore::ScrollingTreeScrollingNode::dumpProperties const):
* page/scrolling/mac/ScrollingCoordinatorMac.mm:
(WebCore::ScrollingCoordinatorMac::commitTreeStateIfNeeded):

Tools:

API test that scrolls an iframe via wheel events, then detached and re-attaches the view.

The two wheel scrolls are necessary to exercise the "stale ScrollingStateScrollingNode
scroll position" issue.

The scrolling tree dumps validate the layout viewport part of the fix.

Also correct some functions where the sense of 'isWaitingForJavaScript' was flipped.

* TestWebKitAPI/TestWebKitAPI.xcodeproj/project.pbxproj:
* TestWebKitAPI/Tests/mac/ScrollingCoordinatorTests.mm: Added.
(TestWebKitAPI::synthesizeWheelEvents):
(TestWebKitAPI::waitForScrollEventAndReturnScrollY):
(TestWebKitAPI::scrollingTreeElidingLastCommittedScrollPosition):
(TestWebKitAPI::TEST):
* TestWebKitAPI/cocoa/TestWKWebView.mm:
(-[WKWebView objectByEvaluatingJavaScript:]):
(-[WKWebView objectByEvaluatingJavaScriptWithUserGesture:]):
(-[WKWebView objectByCallingAsyncFunction:withArguments:error:]):

LayoutTests:

New baselines.

* tiled-drawing/scrolling/clamp-out-of-bounds-scrolls-expected.txt:
* tiled-drawing/scrolling/scrolling-tree-after-scroll-expected.txt:


Canonical link: https://commits.webkit.org/243374@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@284654 268f45cc-cd09-0410-ab3c-d52691b4dbfc
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smfr committed Oct 21, 2021
1 parent be8d260 commit d730c1de2e4dcbfd6581b013a7d04a74f2bfa0ec
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Showing 16 changed files with 273 additions and 20 deletions.
@@ -1,3 +1,15 @@
2021-10-21 Simon Fraser <simon.fraser@apple.com>

Content offset in this codepen when switching tabs
https://bugs.webkit.org/show_bug.cgi?id=231989

Reviewed by Tim Horton.

New baselines.

* tiled-drawing/scrolling/clamp-out-of-bounds-scrolls-expected.txt:
* tiled-drawing/scrolling/scrolling-tree-after-scroll-expected.txt:

2021-10-21 John Wilander <wilander@apple.com>

PCM: Change expectation to pass so we can investigate http/tests/privateClickMeasurement/attribution-conversion-through-image-redirect-in-new-window.html
@@ -55,6 +55,7 @@ Attempted scroll to -5000, -5000
Attempted scroll to 10000, 0

(Frame scrolling node
(scroll position 4223 0)
(scrollable area size 785 585)
(contents size 5008 5021)
(requested scroll position 4223 0)
@@ -75,7 +76,7 @@ Attempted scroll to 10000, 0
Attempted scroll to 0, 10000

(Frame scrolling node
(scroll position 4223 0)
(scroll position 0 4436)
(scrollable area size 785 585)
(contents size 5008 5021)
(requested scroll position 0 4436)
@@ -96,7 +97,7 @@ Attempted scroll to 0, 10000
Attempted scroll to 10000, 10000

(Frame scrolling node
(scroll position 0 4436)
(scroll position 4223 4436)
(scrollable area size 785 585)
(contents size 5008 5021)
(requested scroll position 4223 4436)
@@ -1,5 +1,6 @@

(Frame scrolling node
(scroll position 0 3000)
(scrollable area size 785 600)
(contents size 785 5021)
(requested scroll position 0 3000)
@@ -1,3 +1,51 @@
2021-10-21 Simon Fraser <simon.fraser@apple.com>

Content offset in this codepen when switching tabs
https://bugs.webkit.org/show_bug.cgi?id=231989

Reviewed by Tim Horton.

There were two problems that occurred with async-scrollable iframes when their associated
WKWebView was removed and re-added to the view hierarchy (e.g. when switching tabs).
These resulted in misplaced position:fixed content, and the first user scroll in the
iframe causing the scroll position to jump back to the top.

The positon:fixed issue was caused by an ordering problem in
ScrollingTreeFrameScrollingNode::commitStateBeforeChildren() which resulted in the layout
viewport being computed incorrectly; we called updateViewportForCurrentScrollPosition()
before setting the min and max scroll position, so we'd always clamp the layout viewport to
a location of 0,0.

The second scroll position reset issue was caused by the ScrollingTreeScrollingNode's
m_currentScrollPosition reverting to a stale after re-attaching the iframe's scrolling
subtree. ScrollingTreeScrollingNode::commitStateBeforeChildren() has code to set
m_currentScrollPosition from the state tree node's scroll position on first commit;
the issue was that ScrollingStateScrollingNode's scrollPosition() was not updated on every
scroll, only when something triggered a scrolling tree commit.

Fix by silently updating ScrollingStateScrollingNode's scrollPosition() when we get
notifications back from the scrolling thread that a scroll happened.

Both fixes are tested by the ScrollingCoordinatorTests.ScrollingTreeAfterDetachReattach API test.

* page/scrolling/AsyncScrollingCoordinator.cpp:
(WebCore::AsyncScrollingCoordinator::updateScrollPositionAfterAsyncScroll):
* page/scrolling/ScrollingStateScrollingNode.cpp:
(WebCore::ScrollingStateScrollingNode::syncScrollPosition):
(WebCore::ScrollingStateScrollingNode::hasScrollPositionRequest const):
* page/scrolling/ScrollingStateScrollingNode.h:
* page/scrolling/ScrollingStateTree.cpp:
(WebCore::ScrollingStateTree::insertNode):
* page/scrolling/ScrollingTreeFrameScrollingNode.cpp:
(WebCore::ScrollingTreeFrameScrollingNode::commitStateBeforeChildren): We need to check
state.hasScrollPositionRequest(), otherwise the "cancel animated scroll request" that comes
out of Page::stopKeyboardScrollAnimation() prevents scroll position restoration.
* page/scrolling/ScrollingTreeScrollingNode.cpp:
(WebCore::ScrollingTreeScrollingNode::commitStateBeforeChildren):
(WebCore::ScrollingTreeScrollingNode::dumpProperties const):
* page/scrolling/mac/ScrollingCoordinatorMac.mm:
(WebCore::ScrollingCoordinatorMac::commitTreeStateIfNeeded):

2021-10-21 Sihui Liu <sihui_liu@apple.com>

FileSystemSyncAccessHandle should close platform file handle on close()
@@ -451,6 +451,12 @@ void AsyncScrollingCoordinator::updateScrollPositionAfterAsyncScroll(ScrollingNo
m_page->editorClient().subFrameScrollPositionChanged();
}

auto* node = m_scrollingStateTree->stateNodeForID(scrollingNodeID);
if (is<ScrollingStateScrollingNode>(node)) {
auto& scrollingNode = downcast<ScrollingStateScrollingNode>(*node);
scrollingNode.syncScrollPosition(scrollPosition);
}

if (scrollingNodeID == frameView.scrollingNodeID()) {
reconcileScrollingState(frameView, scrollPosition, layoutViewportOrigin, scrollType, ViewportRectStability::Stable, scrollingLayerPositionAction);
return;
@@ -143,6 +143,11 @@ void ScrollingStateScrollingNode::setScrollPosition(const FloatPoint& scrollPosi
setPropertyChanged(Property::ScrollPosition);
}

void ScrollingStateScrollingNode::syncScrollPosition(const FloatPoint& scrollPosition)
{
m_scrollPosition = scrollPosition;
}

void ScrollingStateScrollingNode::setScrollOrigin(const IntPoint& scrollOrigin)
{
if (m_scrollOrigin == scrollOrigin)
@@ -206,6 +211,11 @@ void ScrollingStateScrollingNode::setRequestedScrollData(const RequestedScrollDa
setPropertyChanged(Property::RequestedScrollPosition);
}

bool ScrollingStateScrollingNode::hasScrollPositionRequest() const
{
return hasChangedProperty(Property::RequestedScrollPosition) && m_requestedScrollData.requestType == ScrollRequestType::PositionUpdate;
}

void ScrollingStateScrollingNode::setIsMonitoringWheelEvents(bool isMonitoringWheelEvents)
{
if (isMonitoringWheelEvents == m_isMonitoringWheelEvents)
@@ -54,6 +54,9 @@ class ScrollingStateScrollingNode : public ScrollingStateNode {
const FloatPoint& scrollPosition() const { return m_scrollPosition; }
WEBCORE_EXPORT void setScrollPosition(const FloatPoint&);

// Does not trigger a scrolling tree commit.
WEBCORE_EXPORT void syncScrollPosition(const FloatPoint&);

const IntPoint& scrollOrigin() const { return m_scrollOrigin; }
WEBCORE_EXPORT void setScrollOrigin(const IntPoint&);

@@ -78,6 +81,8 @@ class ScrollingStateScrollingNode : public ScrollingStateNode {
const RequestedScrollData& requestedScrollData() const { return m_requestedScrollData; }
WEBCORE_EXPORT void setRequestedScrollData(const RequestedScrollData&);

WEBCORE_EXPORT bool hasScrollPositionRequest() const;

bool isMonitoringWheelEvents() const { return m_isMonitoringWheelEvents; }
WEBCORE_EXPORT void setIsMonitoringWheelEvents(bool);

@@ -176,7 +176,7 @@ ScrollingNodeID ScrollingStateTree::insertNode(ScrollingNodeType nodeType, Scrol

if (parentID) {
if (auto unparentedNode = m_unparentedNodes.take(newNodeID)) {
LOG_WITH_STREAM(ScrollingTree, stream << "ScrollingStateTree " << this << " insertNode " << newNodeID << " getting node from unparented nodes");
LOG_WITH_STREAM(ScrollingTree, stream << "ScrollingStateTree " << this << " insertNode reattaching node " << newNodeID);
newNode = unparentedNode.get();
nodeWasReattachedRecursive(*unparentedNode);

@@ -72,10 +72,8 @@ void ScrollingTreeFrameScrollingNode::commitStateBeforeChildren(const ScrollingS
if (state.hasChangedProperty(ScrollingStateNode::Property::FixedElementsLayoutRelativeToFrame))
m_fixedElementsLayoutRelativeToFrame = state.fixedElementsLayoutRelativeToFrame();

if (state.hasChangedProperty(ScrollingStateNode::Property::LayoutViewport)) {
if (state.hasChangedProperty(ScrollingStateNode::Property::LayoutViewport))
m_layoutViewport = state.layoutViewport();
updateViewportForCurrentScrollPosition({ });
}

if (state.hasChangedProperty(ScrollingStateNode::Property::MinLayoutViewportOrigin))
m_minLayoutViewportOrigin = state.minLayoutViewportOrigin();
@@ -85,6 +83,11 @@ void ScrollingTreeFrameScrollingNode::commitStateBeforeChildren(const ScrollingS

if (state.hasChangedProperty(ScrollingStateNode::Property::OverrideVisualViewportSize))
m_overrideVisualViewportSize = state.overrideVisualViewportSize();

if (state.hasChangedProperty(ScrollingStateNode::Property::LayoutViewport)) {
// This requires that minLayoutViewportOrigin and maxLayoutViewportOrigin have been updated.
updateViewportForCurrentScrollPosition({ });
}
}

bool ScrollingTreeFrameScrollingNode::scrollPositionAndLayoutViewportMatch(const FloatPoint& position, std::optional<FloatRect> overrideLayoutViewport)
@@ -67,7 +67,7 @@ void ScrollingTreeScrollingNode::commitStateBeforeChildren(const ScrollingStateN

if (state.hasChangedProperty(ScrollingStateNode::Property::ScrollPosition)) {
m_lastCommittedScrollPosition = state.scrollPosition();
if (m_isFirstCommit && !state.hasChangedProperty(ScrollingStateNode::Property::RequestedScrollPosition))
if (m_isFirstCommit && !state.hasScrollPositionRequest())
m_currentScrollPosition = m_lastCommittedScrollPosition;
}

@@ -336,7 +336,10 @@ void ScrollingTreeScrollingNode::dumpProperties(TextStream& ts, OptionSet<Scroll
ts.dumpProperty("reachable content size", m_reachableContentsSize);
ts.dumpProperty("last committed scroll position", m_lastCommittedScrollPosition);

if (m_scrollOrigin != IntPoint())
if (!m_currentScrollPosition.isZero())
ts.dumpProperty("scroll position", m_currentScrollPosition);

if (!m_scrollOrigin.isZero())
ts.dumpProperty("scroll origin", m_scrollOrigin);

if (m_snapOffsetsInfo.horizontalSnapOffsets.size())
@@ -114,7 +114,7 @@
if (!scrollingStateTree()->hasChangedProperties())
return;

LOG_WITH_STREAM(ScrollingTree, stream << scrollingStateTreeAsText(debugScrollingStateTreeAsTextBehaviors));
LOG_WITH_STREAM(ScrollingTree, stream << "ScrollingCoordinatorMac::commitTreeState: state tree " << scrollingStateTreeAsText(debugScrollingStateTreeAsTextBehaviors));

auto stateTree = scrollingStateTree()->commit(LayerRepresentation::PlatformLayerRepresentation);
scrollingTree()->commitTreeState(WTFMove(stateTree));
@@ -1,3 +1,30 @@
2021-10-21 Simon Fraser <simon.fraser@apple.com>

Content offset in this codepen when switching tabs
https://bugs.webkit.org/show_bug.cgi?id=231989

Reviewed by Tim Horton.

API test that scrolls an iframe via wheel events, then detached and re-attaches the view.

The two wheel scrolls are necessary to exercise the "stale ScrollingStateScrollingNode
scroll position" issue.

The scrolling tree dumps validate the layout viewport part of the fix.

Also correct some functions where the sense of 'isWaitingForJavaScript' was flipped.

* TestWebKitAPI/TestWebKitAPI.xcodeproj/project.pbxproj:
* TestWebKitAPI/Tests/mac/ScrollingCoordinatorTests.mm: Added.
(TestWebKitAPI::synthesizeWheelEvents):
(TestWebKitAPI::waitForScrollEventAndReturnScrollY):
(TestWebKitAPI::scrollingTreeElidingLastCommittedScrollPosition):
(TestWebKitAPI::TEST):
* TestWebKitAPI/cocoa/TestWKWebView.mm:
(-[WKWebView objectByEvaluatingJavaScript:]):
(-[WKWebView objectByEvaluatingJavaScriptWithUserGesture:]):
(-[WKWebView objectByCallingAsyncFunction:withArguments:error:]):

2021-10-21 Fujii Hironori <Hironori.Fujii@sony.com>

[Win] TestWTF.FileSystemTest.* are timing out if run-api-tests is run by a normal user
@@ -86,6 +86,7 @@
0F4FFA9E1ED3AA8500F7111F /* SnapshotViaRenderInContext.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0F4FFA9D1ED3AA8500F7111F /* SnapshotViaRenderInContext.mm */; };
0F5651F71FCE4DDC00310FBC /* NoHistoryItemScrollToFragment.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0F5651F61FCE4DDB00310FBC /* NoHistoryItemScrollToFragment.mm */; };
0F5651F91FCE513500310FBC /* scroll-to-anchor.html in Copy Resources */ = {isa = PBXBuildFile; fileRef = 0F5651F81FCE50E800310FBC /* scroll-to-anchor.html */; };
0FEFAF64271FC2CD005704D7 /* ScrollingCoordinatorTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0FEFAF63271FC2CD005704D7 /* ScrollingCoordinatorTests.mm */; };
0FF1134E22D68679009A81DA /* ScrollViewScrollabilityTests.mm in Sources */ = {isa = PBXBuildFile; fileRef = 0FF1134D22D68679009A81DA /* ScrollViewScrollabilityTests.mm */; };
115EB3431EE0BA03003C2C0A /* ViewportSizeForViewportUnits.mm in Sources */ = {isa = PBXBuildFile; fileRef = 115EB3421EE0B720003C2C0A /* ViewportSizeForViewportUnits.mm */; };
1171B24F219F49CD00CB897D /* FirstMeaningfulPaintMilestone_Bundle.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 11B7FD21219F46DD0069B27F /* FirstMeaningfulPaintMilestone_Bundle.cpp */; };
@@ -1860,6 +1861,7 @@
0FC6C4CE141034AD005B7F0C /* MetaAllocator.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = MetaAllocator.cpp; sourceTree = "<group>"; };
0FE447971B76F1E3009498EB /* ParkingLot.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = ParkingLot.cpp; sourceTree = "<group>"; };
0FEAE3671B7D19CB00CE17F2 /* Condition.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = Condition.cpp; sourceTree = "<group>"; };
0FEFAF63271FC2CD005704D7 /* ScrollingCoordinatorTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ScrollingCoordinatorTests.mm; sourceTree = "<group>"; };
0FF1134D22D68679009A81DA /* ScrollViewScrollabilityTests.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ScrollViewScrollabilityTests.mm; sourceTree = "<group>"; };
0FFC45A41B73EBE20085BD62 /* Lock.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = Lock.cpp; sourceTree = "<group>"; };
115EB3421EE0B720003C2C0A /* ViewportSizeForViewportUnits.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ViewportSizeForViewportUnits.mm; sourceTree = "<group>"; };
@@ -3092,7 +3094,6 @@
F44A530F21B8976900DBB99C /* ClassMethodSwizzler.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ClassMethodSwizzler.h; path = ../TestRunnerShared/cocoa/ClassMethodSwizzler.h; sourceTree = "<group>"; };
F44A531021B8976900DBB99C /* InstanceMethodSwizzler.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; name = InstanceMethodSwizzler.mm; path = ../TestRunnerShared/cocoa/InstanceMethodSwizzler.mm; sourceTree = "<group>"; };
F44A7D1F268D5C6900B49BB8 /* ImageAnalysisTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = ImageAnalysisTests.mm; sourceTree = "<group>"; };
F44A9AF52649BBDD00E7CB16 /* ImmediateActionTests.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ImmediateActionTests.h; sourceTree = "<group>"; };
F44A9AF62649BBDD00E7CB16 /* ImmediateActionTests.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = ImmediateActionTests.mm; sourceTree = "<group>"; };
F44C79FB20F9E50C0014478C /* ParserYieldTokenPlugIn.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = ParserYieldTokenPlugIn.mm; sourceTree = "<group>"; };
F44C79FD20F9E8710014478C /* ParserYieldTokenTests.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ParserYieldTokenTests.h; sourceTree = "<group>"; };
@@ -4828,7 +4829,6 @@
51EB125824C68589000CB030 /* HIDGamepads.mm */,
9B4F8FA3159D52B1002D9F94 /* HTMLCollectionNamedItem.mm */,
9B26FC6B159D061000CC3765 /* HTMLFormCollectionNamedItem.mm */,
F44A9AF52649BBDD00E7CB16 /* ImmediateActionTests.h */,
F44A9AF62649BBDD00E7CB16 /* ImmediateActionTests.mm */,
C507E8A614C6545B005D6B3B /* InspectorBar.mm */,
57F10D921C7E7B3800ECDF30 /* IsNavigationActionTrusted.mm */,
@@ -4848,6 +4848,7 @@
A57A34EF16AF677200C2501F /* PageVisibilityStateWithWindowChanges.mm */,
37C784DE197C8F2E0010A496 /* RenderedImageFromDOMNode.mm */,
3722C8681461E03E00C45D00 /* RenderedImageFromDOMRange.mm */,
0FEFAF63271FC2CD005704D7 /* ScrollingCoordinatorTests.mm */,
261516D515B0E60500A2C201 /* SetAndUpdateCacheModel.mm */,
52B8CF9515868CF000281053 /* SetDocumentURI.mm */,
C540F775152E4DA000A40C8C /* SimplifyMarkup.mm */,
@@ -5845,6 +5846,7 @@
95095F20262FFFA50000D920 /* SampledPageTopColor.mm in Sources */,
CDCFA7AA1E45183200C2433D /* SampleMap.cpp in Sources */,
CE0947372063223B003C9BA0 /* SchemeRegistry.mm in Sources */,
0FEFAF64271FC2CD005704D7 /* ScrollingCoordinatorTests.mm in Sources */,
CDC0932B21C872C10030C4B0 /* ScrollingDoesNotPauseMedia.mm in Sources */,
7CCE7F121A411AE600447C4C /* ScrollPinningBehaviors.cpp in Sources */,
F434CA1A22E65BCA005DDB26 /* ScrollToRevealSelection.mm in Sources */,

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