Revert of Introduce LayerListImpl (patchset #11 id:200001 of https://codereview.chromium.org/1746603002/ )

Reason for revert:
I'm going to try another, less code churny approach to the layer list refactor.

Original issue's description:
> Introduce LayerListImpl
>
> In this cl, the LayerTreeImpl constructs a LayerListImpl.
> The idea being that most plumbing won't need to change at
> first to get the list to where it needs to be. The first
> consumer of the LayerTreeImpl that I'm attempting to
> teach to speak LayerListImpl-ese is the LayerImpl. That
> has not been completely finished in this cl so that it
> doesn't become too big and difficult to review.
>
> NB: since the actual storage of the LayerImpls doesn't
> change in this cl (they're still in the LayerTreeImpl),
> there's no need to guard this work behind a flag.
>
> BUG=557194
> CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
>
> Committed: https://crrev.com/299bf1f63b8253c77530b904874f3435f9bde6d3
> Cr-Commit-Position: refs/heads/master@{#378398}

TBR=weiliangc@chromium.org,ajuma@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=557194

Review URL: https://codereview.chromium.org/1751243002

Cr-Commit-Position: refs/heads/master@{#378608}

1 files changed, 4 insertions, 6 deletions

diff --git a/cc/layers/layer.cc b/cc/layers/layer.cc
index 1441ccd..3842741 100644
--- a/cc/layers/layer.cc
+++ b/cc/layers/layer.cc
@@ -1289,8 +1289,7 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
 
   LayerImpl* scroll_parent = nullptr;
   if (scroll_parent_) {
-    scroll_parent =
-        layer->layer_tree_impl()->list()->LayerById(scroll_parent_->id());
+    scroll_parent = layer->layer_tree_impl()->LayerById(scroll_parent_->id());
     DCHECK(scroll_parent);
   }
 
@@ -1302,7 +1301,7 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
          ++it) {
       DCHECK_EQ((*it)->scroll_parent(), this);
       LayerImpl* scroll_child =
-          layer->layer_tree_impl()->list()->LayerById((*it)->id());
+          layer->layer_tree_impl()->LayerById((*it)->id());
       DCHECK(scroll_child);
       scroll_children->insert(scroll_child);
     }
@@ -1314,7 +1313,7 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
   LayerImpl* clip_parent = nullptr;
   if (clip_parent_) {
     clip_parent =
-        layer->layer_tree_impl()->list()->LayerById(clip_parent_->id());
+        layer->layer_tree_impl()->LayerById(clip_parent_->id());
     DCHECK(clip_parent);
   }
 
@@ -1324,8 +1323,7 @@ void Layer::PushPropertiesTo(LayerImpl* layer) {
     for (std::set<Layer*>::iterator it = clip_children_->begin();
         it != clip_children_->end(); ++it) {
       DCHECK_EQ((*it)->clip_parent(), this);
-      LayerImpl* clip_child =
-          layer->layer_tree_impl()->list()->LayerById((*it)->id());
+      LayerImpl* clip_child = layer->layer_tree_impl()->LayerById((*it)->id());
       DCHECK(clip_child);
       clip_children->insert(clip_child);
     }