Add DidSaveScrollOrScaleState flag to prevent restoreScrollPositionAndViewState restore from default

third_party/WebKit/Source/core/loader/FrameLoader.cpp

Index: third_party/WebKit/Source/core/loader/FrameLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/FrameLoader.cpp b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
index 0610418fd1c887b2c6234a917927ef78991a3ac6..4997e93adea15b876ca35911bb7cefd1f6b972cb 100644
--- a/third_party/WebKit/Source/core/loader/FrameLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
@@ -743,7 +743,7 @@ void FrameLoader::checkCompleted() {
     m_progressTracker->progressCompleted();
     // Retry restoring scroll offset since finishing loading disables content
     // size clamping.
-    restoreScrollPositionAndViewState();
+    setScrollFromNavigation(NavigationToDifferentDocument);

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

Are you sure this is the correct navigation type?
checkCompleted is also invoked from |FrameLoader::loadInSameDocument| which
suggests otherwise.

 
     m_loadType = FrameLoadTypeStandard;
     m_frame->domWindow()->finishedLoading();
@@ -887,7 +887,7 @@ void FrameLoader::loadInSameDocument(
                                         : SerializedScriptValue::nullValue());
 
   if (historyLoadType == HistorySameDocumentLoad)
-    restoreScrollPositionAndViewState();
+    setScrollFromNavigation(NavigationWithinSameDocument);
 
   // We need to scroll to the fragment whether or not a hash change occurred,
   // since the user might have scrolled since the previous navigation.
@@ -1376,6 +1376,11 @@ FrameLoadType FrameLoader::loadType() const {
   return m_loadType;
 }
 
+void FrameLoader::setScrollFromNavigation(LoadStartType loadStartType) {
+  processFragment(m_frame->document()->url(), loadStartType);
+  restoreScrollPositionAndViewState();
+}
+
 void FrameLoader::restoreScrollPositionAndViewState() {
   FrameView* view = m_frame->view();
   if (!m_frame->page() || !view || !view->layoutViewportScrollableArea() ||