[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 17f6c480a39afcbce87816f66005f4d78919f0e6..fc7cb6c38eba0d2484deaef53dc0b00181869e70 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;
@@ -30,13 +30,15 @@ TextureLayerImpl::TextureLayerImpl(LayerTreeImpl* tree_impl,
   vertex_opacity_[3] = 1.0f;
 }
 
-TextureLayerImpl::~TextureLayerImpl() { FreeTextureMailbox(); }
+TextureLayerImpl::~TextureLayerImpl() {
+  FreeMailbox();
+}
 
 void TextureLayerImpl::SetTextureMailbox(const TextureMailbox& mailbox) {
   DCHECK(uses_mailbox_);
-  DCHECK(mailbox.IsEmpty() || !mailbox.Equals(texture_mailbox_));
-  FreeTextureMailbox();
-  texture_mailbox_ = mailbox;
+  DCHECK(!mailbox.IsValid() || !mailbox.Equals(mailbox_));
+  FreeMailbox();
+  mailbox_ = mailbox;
   own_mailbox_ = true;
 }
 
@@ -56,7 +58,7 @@ void TextureLayerImpl::PushPropertiesTo(LayerImpl* layer) {
   texture_layer->set_vertex_opacity(vertex_opacity_);
   texture_layer->set_premultiplied_alpha(premultiplied_alpha_);
   if (uses_mailbox_ && own_mailbox_) {
-    texture_layer->SetTextureMailbox(texture_mailbox_);
+    texture_layer->SetTextureMailbox(mailbox_);
     own_mailbox_ = false;
   } else {
     texture_layer->set_texture_id(texture_id_);
@@ -140,19 +142,19 @@ void TextureLayerImpl::DidBecomeActive() {
     return;
   DCHECK(!external_texture_resource_);
   ResourceProvider* resource_provider = layer_tree_impl()->resource_provider();
-  if (!texture_mailbox_.IsEmpty()) {
+  if (mailbox_.IsValid()) {
     external_texture_resource_ =
-        resource_provider->CreateResourceFromTextureMailbox(texture_mailbox_);
+        resource_provider->CreateResourceFromTextureMailbox(mailbox_);
   }
   own_mailbox_ = false;
 }
 
-void TextureLayerImpl::FreeTextureMailbox() {
+void TextureLayerImpl::FreeMailbox() {
   if (!uses_mailbox_)
     return;
   if (own_mailbox_) {
     DCHECK(!external_texture_resource_);
-    texture_mailbox_.RunReleaseCallback(texture_mailbox_.sync_point(), false);
+    mailbox_.RunReleaseCallback(mailbox_.sync_point(), false);
   } else if (external_texture_resource_) {
     DCHECK(!own_mailbox_);
     ResourceProvider* resource_provider =