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..a9b006a5e0fd2e577dc4ce1481377b358d96025b 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -273,6 +273,11 @@ void FrameView::reset() {
   m_orthogonalWritingModeRootList.clear();
 }
 
+void FrameView::setScrollFromNavigation() {

[majidvp, 2017/01/24 21:53:52]

nit: please match the declaration order in header file.

+  scrollToFragmentAnchor();

[majidvp, 2017/01/24 21:53:52]

In this case, 
scrollToFragment does not honor history.scrollRestoration

Can it cause an issue?

[chaopeng, 2017/01/25 15:22:38]

No, in this case m_fragmentAnchor is null and scrollToFragment will do nothing
because we dont set m_fragmentAnchor in this case. 
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/frame/Fra...

[majidvp, 2017/01/25 20:31:59]

Are you sure? If the fragmentAnchor is always nil in such cases then why do we
even bother to call scrollToFragmentAnchor?

+  frame().loader().restoreScrollPositionAndViewState();
+}
+
 // Call function for each non-throttled frame view in pre tree order.
 // Note it needs a null check of the frame's layoutView to access it in case of
 // detached frames.
@@ -547,7 +552,7 @@ void FrameView::setFrameRect(const IntRect& newRect) {
     if (m_frame->isMainFrame())
       m_frame->host()->visualViewport().mainFrameDidChangeSize();
 
-    frame().loader().restoreScrollPositionAndViewState();
+    setScrollFromNavigation();
   }
 }
 
@@ -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();
+  setScrollFromNavigation();
 }
 
 void FrameView::adjustViewSize() {