Tie scroll anchoring adjustments to frame lifecycle instead of layout.

third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp

Index: third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp
diff --git a/third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp b/third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp
index bc0c6fccbfdae428e580591c2cb613fd7549a6c5..a5ddd930564966c71557021ef3c76bc54ad15e41 100644
--- a/third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp
+++ b/third_party/WebKit/Source/core/frame/LocalDOMWindow.cpp
@@ -973,7 +973,7 @@ double LocalDOMWindow::scrollX() const {
   if (!view)
     return 0;
 
-  document()->updateStyleAndLayoutIgnorePendingStylesheets();
+  document()->updateScrollPosition();
 
   double viewportX =
       view->layoutViewportScrollableArea()->scrollOffset().width();
@@ -991,7 +991,7 @@ double LocalDOMWindow::scrollY() const {
   if (!view)
     return 0;
 
-  document()->updateStyleAndLayoutIgnorePendingStylesheets();
+  document()->updateScrollPosition();
 
   double viewportY =
       view->layoutViewportScrollableArea()->scrollOffset().height();