Fold ScrollingCoordinatorChromium into ScrollingCoordinator and devirtualize

Source/WebCore/dom/Document.cpp

Index: Source/WebCore/dom/Document.cpp
diff --git a/Source/WebCore/dom/Document.cpp b/Source/WebCore/dom/Document.cpp
index 7f052417c4158fa91d3fe090121ff1c763695cb3..6fd4c7e42c8bc132a14c86d98bf3a42342d05343 100644
--- a/Source/WebCore/dom/Document.cpp
+++ b/Source/WebCore/dom/Document.cpp
@@ -4104,11 +4104,9 @@ void Document::setInPageCache(bool flag)
             // function. It would be nice if there was more symmetry here.
             // https://bugs.webkit.org/show_bug.cgi?id=98698
             v->cacheCurrentScrollPosition();
-            if (page && page->mainFrame() == m_frame) {
+            if (page && page->mainFrame() == m_frame)
                 v->resetScrollbarsAndClearContentsSize();
-                if (ScrollingCoordinator* scrollingCoordinator = page->scrollingCoordinator())
-                    scrollingCoordinator->clearStateTree();
-            } else
+            else
                 v->resetScrollbars();
         }
         m_styleRecalcTimer.stop();