Invalidate DisplayItemClient when selection state changes

Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 2997 matching lines @@
 
     ASSERT(!node());
     return createPositionWithAffinity(0, DOWNSTREAM);
 }
 
 CursorDirective LayoutObject::getCursor(const LayoutPoint&, Cursor&) const
 {
     return SetCursorBasedOnStyle;
 }
 
+void LayoutObject::setSelectionState(SelectionState state)
+{
+    if (selectionState() == state)
+        return;
+
+    m_bitfields.setSelectionState(state);
+    invalidateDisplayItemClient(DisplayItemClientData(*this));

[Xianzhu, 2015/03/18 16:10:07]

Alternative way is to call 'if slimmingPaintEnabled)
setShouldDoFullPaintInvalidation()' here. I prefer it because it's faster.
invalidateDisplayItemClient involves walking up the layout tree to find paint
invalidation container.

+}
+
+
 bool LayoutObject::canUpdateSelectionOnRootLineBoxes() const
 {
     if (needsLayout())
         return false;
 
     const LayoutBlock* containingBlock = this->containingBlock();
     return containingBlock ? !containingBlock->needsLayout() : false;
 }
 
 // We only create "generated" child renderers like one for first-letter if:
@@ skipping 190 matching lines @@
 {
     if (object1) {
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif