First step of PaintInvalidator implementation

third_party/WebKit/Source/core/layout/LayoutBlockFlowLine.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 2058 matching lines @@
         return false;
 
     return LayoutBlock::paintedOutputOfObjectHasNoEffect();
 }
 
 PaintInvalidationReason LayoutBlockFlow::invalidatePaintIfNeeded(const PaintInvalidationState& paintInvalidationState)
 {
     if (containsFloats())
         paintInvalidationState.paintingLayer().setNeedsPaintPhaseFloat();
 
-    PaintInvalidationReason reason = LayoutBlock::invalidatePaintIfNeeded(paintInvalidationState);
-    if (reason == PaintInvalidationNone || reason == PaintInvalidationDelayedFull)
-        return reason;
-
-    RootInlineBox* line = firstRootBox();
-    if (!line || !line->isFirstLineStyle())
-        return reason;
-    // It's the RootInlineBox that paints the ::first-line background. Note that since it may be
-    // expensive to figure out if the first line is affected by any ::first-line selectors at all,
-    // we just invalidate it unconditionally, since that's typically cheaper.
-    invalidateDisplayItemClient(*line, reason);
-    return reason;
+    return LayoutBlock::invalidatePaintIfNeeded(paintInvalidationState);
 }
 
 } // namespace blink