Discard scrolling to the saved scroll points if there is any selection done by user.

Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1752 matching lines @@
         rect = revealExtentOption == RevealExtent ? VisiblePosition(extent()).absoluteCaretBounds() : enclosingIntRect(unclippedBounds());
         break;
     }
 
     Position start = this->start();
     ASSERT(start.deprecatedNode());
     if (start.deprecatedNode() && start.deprecatedNode()->renderer()) {
         // FIXME: This code only handles scrolling the startContainer's layer, but
         // the selection rect could intersect more than just that.
         // See <rdar://problem/4799899>.
+        m_frame->view()->setWasScrolledByUser(true);

[yoichio, 2015/03/11 04:16:52]

Could you confirm this code path is called by only user action?

[pals, 2015/03/11 06:09:28]

I am not sure about this, I am not very familiar about this part of the code and
there are many calls to revealSelection(). As there are no layout test failure,
I thought this patch can be a fix.

         if (start.deprecatedNode()->renderer()->scrollRectToVisible(rect, alignment, alignment))
             updateAppearance();
     }
 }
 
 void FrameSelection::setSelectionFromNone()
 {
     // Put a caret inside the body if the entire frame is editable (either the
     // entire WebView is editable or designMode is on for this document).
 
@@ skipping 138 matching lines @@
     sel.showTreeForThis();
 }
 
 void showTree(const blink::FrameSelection* sel)
 {
     if (sel)
         sel->showTreeForThis();
 }
 
 #endif