Replace various ScrollableArea scroll methods with setScrollPosition

Source/modules/accessibility/AXObject.cpp

 /*
  * Copyright (C) 2008, 2009, 2011 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
@@ skipping 1068 matching lines @@
 
     return IntPoint(area->maximumScrollPosition().x(), area->maximumScrollPosition().y());
 }
 
 void AXObject::setScrollOffset(const IntPoint& offset) const
 {
     ScrollableArea* area = getScrollableAreaIfScrollable();
     if (!area)
         return;
 
-    area->setScrollPosition(DoublePoint(offset.x(), offset.y()));
+    area->setScrollPosition(DoublePoint(offset.x(), offset.y()), ProgrammaticScroll);

[dmazzoni, 2015/06/09 19:40:23]

What are the implications of this being a programmatic scroll vs user scroll?

Typically we assume accessibility is the agent of the user - for example if a
user with a motor impairment issues a voice command to scroll down the page and
that triggers using accessibility APIs, we should treat that the same as if they
pressed PageDown or flicked their mouse scroll wheel.

For example, we call this before triggering a button press via accessibility:

UserGestureIndicator gestureIndicator(DefinitelyProcessingNewUserGesture);

Does that sound okay or am I misunderstanding the difference between user and
programmatic here?

[bokan, 2015/06/09 20:03:01]

Hmm...right now the only implication here is which ScrollAnimator gets used. We
have separate animators for user and programmatic scrolls (I'm not sure why) and
a scroll through one cancels any animations on the other.

The call I'm replacing here was taking the programmatic scroll path. In that
case, should this and AXScrollbar be a UserScroll? Functionally, I don't think
it makes much difference right now but we may key more info off this in the
future.

 }
 
 //
 // Modify or take an action on an object.
 //
 
 bool AXObject::press() const
 {
     Element* actionElem = actionElement();
     if (!actionElem)
@@ skipping 371 matching lines @@
 }
 
 const AtomicString& AXObject::internalRoleName(AccessibilityRole role)
 {
     static const Vector<AtomicString>* internalRoleNameVector = createInternalRoleNameVector();
 
     return internalRoleNameVector->at(role);
 }
 
 } // namespace blink