Move second internal recursion to a precomputation in layer_tree_host_common.cc

cc/layer.cc

 // Copyright 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layer.h"
 
 #include "cc/active_animation.h"
 #include "cc/animation_events.h"
 #include "cc/layer_animation_controller.h"
 #include "cc/layer_impl.h"
@@ skipping 46 matching lines @@
     , m_replicaLayer(0)
     , m_drawOpacity(0)
     , m_drawOpacityIsAnimating(false)
     , m_renderTarget(0)
     , m_drawTransformIsAnimating(false)
     , m_screenSpaceTransformIsAnimating(false)
     , m_isClipped(false)
     , m_rasterScale(1.0)
     , m_automaticallyComputeRasterScale(false)
     , m_boundsContainPageScale(false)
+    , m_numDescendantsThatDrawContent(0)
     , m_layerAnimationDelegate(0)
     , m_layerScrollClient(0)
 {
     if (m_layerId < 0) {
         s_nextLayerId = 1;
         m_layerId = s_nextLayerId++;
     }
 }
 
 Layer::~Layer()
@@ skipping 614 matching lines @@
     setNeedsDisplay();
 }
 
 void Layer::createRenderSurface()
 {
     DCHECK(!m_renderSurface);
     m_renderSurface = make_scoped_ptr(new RenderSurface(this));
     setRenderTarget(this);
 }
 
-int Layer::descendantsDrawContent()
-{
-    int result = 0;
-    for (size_t i = 0; i < m_children.size(); ++i) {
-        if (m_children[i]->drawsContent())
-            ++result;
-        result += m_children[i]->descendantsDrawContent();
-        if (result > 1)
-            return result;
-    }
-    return result;
-}
-
 int Layer::id() const
 {
     return m_layerId;
 }
 
 float Layer::opacity() const
 {
     return m_opacity;
 }
 
@@ skipping 114 matching lines @@
 {
     return 0;
 }
 
 void sortLayers(std::vector<scoped_refptr<Layer> >::iterator, std::vector<scoped_refptr<Layer> >::iterator, void*)
 {
     // Currently we don't use z-order to decide what to paint, so there's no need to actually sort Layers.
 }
 
 }  // namespace cc