Add DidSaveScrollOrScaleState flag to prevent restoreScrollPositionAndViewState restore from default

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

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index 9985fcf17ee6f5096f710bf35ea8f955a09db7b3..fd33a47925f31116d4d81996181b645a2f9704eb 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -520,6 +520,11 @@ void FrameView::invalidateRect(const IntRect& rect) {
   layoutItem.invalidatePaintRectangle(LayoutRect(paintInvalidationRect));
 }
 
+void FrameView::setScrollAfterSizeChange() {
+  scrollToFragmentAnchor();
+  frame().loader().restoreScrollPositionAndViewState();
+}
+
 void FrameView::setFrameRect(const IntRect& newRect) {
   IntRect oldRect = frameRect();
   if (newRect == oldRect)
@@ -547,7 +552,7 @@ void FrameView::setFrameRect(const IntRect& newRect) {
     if (m_frame->isMainFrame())
       m_frame->host()->visualViewport().mainFrameDidChangeSize();
 
-    frame().loader().restoreScrollPositionAndViewState();
+    setScrollAfterSizeChange();
   }
 }
 
@@ -668,10 +673,7 @@ void FrameView::setContentsSize(const IntSize& size) {
 
   page->chromeClient().contentsSizeChanged(m_frame.get(), size);
 
-  // Ensure the scrollToFragmentAnchor is called before
-  // restoreScrollPositionAndViewState when reload
-  scrollToFragmentAnchor();
-  frame().loader().restoreScrollPositionAndViewState();
+  setScrollAfterSizeChange();
 }
 
 void FrameView::adjustViewSize() {