Set up clip and scroll parents on the blink side.

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index 20de5e0aa1ebf4ab7c9bb6eb9ecbf401bddd81ec..07e2f895cd3fc77cfe242fdd37e1b01f207c9b79 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -3931,6 +3931,10 @@ void WebViewImpl::setIsAcceleratedCompositingActive(bool active)
 
 void WebViewImpl::updateMainFrameScrollPosition(const IntPoint& scrollPosition, bool programmaticScroll)
 {
+    TRACE_EVENT1("impl-scroll",
+        "WebViewImpl::updateMainFrameScrollPosition",
+        "programmatic", programmaticScroll);
+
     FrameView* frameView = page()->mainFrame()->view();
     if (!frameView)
         return;
@@ -3950,7 +3954,7 @@ void WebViewImpl::applyScrollAndScale(const WebSize& scrollDelta, float pageScal
         return;
 
     if (pageScaleDelta == 1) {
-        TRACE_EVENT_INSTANT2("webkit", "WebViewImpl::applyScrollAndScale::scrollBy", "x", scrollDelta.width, "y", scrollDelta.height);
+        TRACE_EVENT_INSTANT2("webkit,impl-scroll", "WebViewImpl::applyScrollAndScale::scrollBy", "x", scrollDelta.width, "y", scrollDelta.height);
         WebSize webScrollOffset = mainFrame()->scrollOffset();
         IntPoint scrollOffset(webScrollOffset.width + scrollDelta.width, webScrollOffset.height + scrollDelta.height);
         updateMainFrameScrollPosition(scrollOffset, false);