Remove null check for LayerTreeView from RenderFrameImpl

The LayerTreeView would be null only if the RenderWidget was closed.
That shouldn't be the case while there is a RenderFrame using it (bug
939262)! But if there is let's hear about it.

Bug: 939262
Change-Id: I7c234d853451d7b005c369327bb3c82fc1e4d65e
Reviewed-by: Daniel Cheng <>
Commit-Queue: danakj <>
Cr-Commit-Position: refs/heads/master@{#642182}
1 file changed