[Aura] Added Support for rendering software compositor frames as cc::TextureLayers.

cc/layers/texture_layer_impl.cc

Index: cc/layers/texture_layer_impl.cc
diff --git a/cc/layers/texture_layer_impl.cc b/cc/layers/texture_layer_impl.cc
index 44062975bf8949c2899f854e2f7c92eb5c473c9e..e4d252ab550c30f1cfb98d8da611426ed5b49990 100644
--- a/cc/layers/texture_layer_impl.cc
+++ b/cc/layers/texture_layer_impl.cc
@@ -16,13 +16,13 @@ TextureLayerImpl::TextureLayerImpl(LayerTreeImpl* tree_impl,
                                    int id,
                                    bool uses_mailbox)
     : LayerImpl(tree_impl, id),
+      uses_mailbox_(uses_mailbox),
       texture_id_(0),
       external_texture_resource_(0),
       premultiplied_alpha_(true),
       flipped_(true),
       uv_top_left_(0.f, 0.f),
       uv_bottom_right_(1.f, 1.f),
-      uses_mailbox_(uses_mailbox),
       own_mailbox_(false) {
   vertex_opacity_[0] = 1.0f;
   vertex_opacity_[1] = 1.0f;
@@ -34,7 +34,9 @@ TextureLayerImpl::~TextureLayerImpl() { FreeTextureMailbox(); }
 
 void TextureLayerImpl::SetTextureMailbox(const TextureMailbox& mailbox) {
   DCHECK(uses_mailbox_);
-  DCHECK(mailbox.IsEmpty() || !mailbox.Equals(texture_mailbox_));
+  DCHECK(!mailbox.IsValid() ||
+         mailbox.IsSharedMemory() ||
+         !mailbox.ContainsMailbox(texture_mailbox_.name()));
   FreeTextureMailbox();
   texture_mailbox_ = mailbox;
   own_mailbox_ = true;
@@ -146,7 +148,7 @@ void TextureLayerImpl::DidBecomeActive() {
     return;
   DCHECK(!external_texture_resource_);
   ResourceProvider* resource_provider = layer_tree_impl()->resource_provider();
-  if (!texture_mailbox_.IsEmpty()) {
+  if (texture_mailbox_.IsValid()) {
     external_texture_resource_ =
         resource_provider->CreateResourceFromTextureMailbox(texture_mailbox_);
   }