CC AnimationHost: Fix ProgrammaticScrollAnimator detach scope.

third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp

Index: third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp
diff --git a/third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp b/third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp
index 151fa5cf9902d021ac0b9cf9b8de0247c4b89f62..f3b10cccc90ec0c0e0251c0977b3f09a61610a7d 100644
--- a/third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp
+++ b/third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp
@@ -94,14 +94,7 @@ ScrollingCoordinator::ScrollingCoordinator(Page* page)
     , m_wasFrameScrollable(false)
     , m_lastMainThreadScrollingReasons(0)
 {
-    if (RuntimeEnabledFeatures::compositorAnimationTimelinesEnabled() && Platform::current()->isThreadedAnimationEnabled()) {
-        ASSERT(m_page);
-        if (m_page->mainFrame()->isLocalFrame()) {
-            ASSERT(Platform::current()->compositorSupport());
-            m_programmaticScrollAnimatorTimeline = adoptPtr(Platform::current()->compositorSupport()->createAnimationTimeline());
-            m_page->chromeClient().attachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
-        }
-    }
+    createProgrammaticScrollAnimatorTimeline();
 }
 
 ScrollingCoordinator::~ScrollingCoordinator()
@@ -727,15 +720,16 @@ void ScrollingCoordinator::setShouldUpdateScrollLayerPositionOnMainThread(MainTh
     }
 }
 
+void ScrollingCoordinator::willCloseLayerTreeView()
+{
+    destroyProgrammaticScrollAnimatorTimeline();
+}
+
 void ScrollingCoordinator::willBeDestroyed()
 {
     ASSERT(m_page);
 
-    if (m_programmaticScrollAnimatorTimeline) {
-        ASSERT(m_page->mainFrame()->isLocalFrame());
-        m_page->chromeClient().detachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
-        m_programmaticScrollAnimatorTimeline.clear();
-    }
+    destroyProgrammaticScrollAnimatorTimeline();
 
     m_page = nullptr;
     for (const auto& scrollbar : m_horizontalScrollbars)
@@ -1081,4 +1075,26 @@ bool ScrollingCoordinator::frameViewIsDirty() const
     return false;
 }
 
+void ScrollingCoordinator::createProgrammaticScrollAnimatorTimeline()
+{
+    if (RuntimeEnabledFeatures::compositorAnimationTimelinesEnabled() && Platform::current()->isThreadedAnimationEnabled()) {
+        ASSERT(m_page);
+        if (m_page->mainFrame()->isLocalFrame()) {
+            ASSERT(Platform::current()->compositorSupport());
+            m_programmaticScrollAnimatorTimeline = adoptPtr(Platform::current()->compositorSupport()->createAnimationTimeline());
+            m_page->chromeClient().attachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
+        }
+    }
+}
+
+void ScrollingCoordinator::destroyProgrammaticScrollAnimatorTimeline()
+{
+    if (m_programmaticScrollAnimatorTimeline) {
+        ASSERT(m_page);
+        ASSERT(m_page->mainFrame()->isLocalFrame());
+        m_page->chromeClient().detachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
+        m_programmaticScrollAnimatorTimeline.clear();
+    }
+}
+
 } // namespace blink