cc: Add id->LayerImpl map to LayerTreeImpl

cc/layer_impl.cc

Index: cc/layer_impl.cc
diff --git a/cc/layer_impl.cc b/cc/layer_impl.cc
index 3ee3c751f95685c4665c6cf0562db23b2ed1e755..0c22ccf70556f5fc3951c10c50fee00f4f4c3d59 100644
--- a/cc/layer_impl.cc
+++ b/cc/layer_impl.cc
@@ -56,6 +56,7 @@ LayerImpl::LayerImpl(LayerTreeImpl* treeImpl, int id)
 {
     DCHECK(m_layerId > 0);
     DCHECK(m_layerTreeImpl);
+    m_layerTreeImpl->RegisterLayer(this);
 }
 
 LayerImpl::~LayerImpl()
@@ -63,6 +64,7 @@ LayerImpl::~LayerImpl()
 #ifndef NDEBUG
     DCHECK(!m_betweenWillDrawAndDidDraw);
 #endif
+    m_layerTreeImpl->UnregisterLayer(this);
 }
 
 void LayerImpl::addChild(scoped_ptr<LayerImpl> child)
@@ -494,32 +496,46 @@ void LayerImpl::setBounds(const gfx::Size& bounds)
 
 void LayerImpl::setMaskLayer(scoped_ptr<LayerImpl> maskLayer)
 {
-    if (maskLayer)
-        DCHECK_EQ(layerTreeImpl(), maskLayer->layerTreeImpl());
-    m_maskLayer = maskLayer.Pass();
+    int newLayerId = maskLayer ? maskLayer->id() : -1;
 
-    int newLayerId = m_maskLayer ? m_maskLayer->id() : -1;
-    if (newLayerId == m_maskLayerId)
+    if (maskLayer) {
+        DCHECK_EQ(layerTreeImpl(), maskLayer->layerTreeImpl());
+        DCHECK_NE(newLayerId, m_maskLayerId);
+    } else if (newLayerId == m_maskLayerId)

[danakj, 2012/12/13 23:57:11]

This is "if (!maskLayer && newLayerId == m_maskLayerId)"

I don't think you meant else if?

[enne (OOO), 2012/12/14 00:21:12]

No, I meant else if.  This is the case where "if you don't have a mask layer and
you're assigning a null mask layer, then return and don't call
noteLayerPropertyBlahBlah".

If I didn't do the else if, then you could drop maskLayer on the floor, like
you're worried about below.

[danakj, 2012/12/14 00:23:15]

OOhh. ok!

         return;

[danakj, 2012/12/13 23:57:11]

If the ids match, we're going to free the maskLayer passed in here? This seems
super weird. We used to always assign the pointer before.

I suspect this is never called with a non-NULL pointer where the layerId ==
maskLayerId. It seems impossible without breaking a pointer out of scoped_ptr.
So this check seems weird to me.

 
+    m_maskLayer = maskLayer.Pass();
     m_maskLayerId = newLayerId;
     noteLayerPropertyChangedForSubtree();
 }
 
+scoped_ptr<LayerImpl> LayerImpl::takeMaskLayer()
+{
+  m_maskLayerId = -1;
+  return m_maskLayer.Pass();
+}
+
 void LayerImpl::setReplicaLayer(scoped_ptr<LayerImpl> replicaLayer)
 {
-    if (replicaLayer)
-        DCHECK_EQ(layerTreeImpl(), replicaLayer->layerTreeImpl());
-    m_replicaLayer = replicaLayer.Pass();
+    int newLayerId = replicaLayer ? replicaLayer->id() : -1;
 
-    int newLayerId = m_replicaLayer ? m_replicaLayer->id() : -1;
-    if (newLayerId == m_replicaLayerId)
+    if (replicaLayer) {
+        DCHECK_EQ(layerTreeImpl(), replicaLayer->layerTreeImpl());
+        DCHECK_NE(newLayerId, m_replicaLayerId);
+    } else if (newLayerId == m_replicaLayerId)
         return;
 
+    m_replicaLayer = replicaLayer.Pass();
     m_replicaLayerId = newLayerId;
     noteLayerPropertyChangedForSubtree();
 }
 
+scoped_ptr<LayerImpl> LayerImpl::takeReplicaLayer()
+{
+  m_replicaLayerId = -1;
+  return m_replicaLayer.Pass();
+}
+
 void LayerImpl::setDrawsContent(bool drawsContent)
 {
     if (m_drawsContent == drawsContent)