Move second internal recursion to a precomputation in layer_tree_host_common.cc

cc/layer_impl.cc

Index: cc/layer_impl.cc
diff --git a/cc/layer_impl.cc b/cc/layer_impl.cc
index a1dffea69f549bbdd673c81d5076b54092677f23..00ef261ca1919b96a4795889527583448ede2af5 100644
--- a/cc/layer_impl.cc
+++ b/cc/layer_impl.cc
@@ -59,6 +59,7 @@ LayerImpl::LayerImpl(int id)
 #ifndef NDEBUG
     , m_betweenWillDrawAndDidDraw(false)
 #endif
+    , m_numDescendantsThatDrawContent(0)
     , m_layerAnimationController(LayerAnimationController::create(this))
 {
     DCHECK(m_layerId > 0);
@@ -112,19 +113,6 @@ void LayerImpl::createRenderSurface()
     setRenderTarget(this);
 }
 
-int LayerImpl::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;
-}
-
 scoped_ptr<SharedQuadState> LayerImpl::createSharedQuadState() const
 {
   scoped_ptr<SharedQuadState> state = SharedQuadState::Create();