Simplify CompositingReasonFinder::requiresCompositingForFrame

Source/core/rendering/compositing/RenderLayerCompositor.cpp

 /*
  * Copyright (C) 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 201 matching lines @@
     , m_isTrackingRepaints(false)
     , m_rootLayerAttachment(RootLayerUnattached)
 {
 }
 
 RenderLayerCompositor::~RenderLayerCompositor()
 {
     ASSERT(m_rootLayerAttachment == RootLayerUnattached);
 }
 
-void RenderLayerCompositor::enableCompositingMode(bool enable /* = true */)
+void RenderLayerCompositor::enableCompositingMode(bool enable)
 {
-    if (enable != m_compositing) {
-        m_compositing = enable;
+    if (enable == m_compositing)
+        return;
 
-        if (m_compositing) {
-            ensureRootLayer();
-            notifyIFramesOfCompositingChange();
-        } else
-            destroyRootLayer();
-    }
+    m_compositing = enable;
+
+    if (m_compositing)
+        ensureRootLayer();
+    else
+        destroyRootLayer();
+
+    notifyIFramesOfCompositingChange();
 }
 
 void RenderLayerCompositor::cacheAcceleratedCompositingFlags()
 {
     bool hasAcceleratedCompositing = false;
     bool showRepaintCounter = false;
     bool forceCompositingMode = false;
 
     if (Settings* settings = m_renderView.document().settings()) {
         hasAcceleratedCompositing = settings->acceleratedCompositingEnabled();
@@ skipping 1997 matching lines @@
     } else if (graphicsLayer == m_scrollLayer.get()) {
         name = "LocalFrame Scrolling Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace WebCore