cc: Mark layers with invalid property tree indices as non-drawable.

We already skip these layers during UpdateDrawProperties to prevent
crashes. Mark these layers as non-drawing so they are skipped by the
rest of the system.

BUG=730020
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2925213002
Cr-Commit-Position: refs/heads/master@{#478657}

cc/trees/draw_property_utils.cc

@@ -851,6 +851,7 @@ void FindLayersThatNeedUpdates(LayerTreeImpl* layer_tree_impl,
     // removed as layer_impl should not be nullptr here.
     if (!layer_impl || !layer_impl->HasValidPropertyTreeIndices())
       continue;
+
     if (!IsRootLayer(layer_impl) &&
         LayerShouldBeSkippedForDrawPropertiesComputation(
             layer_impl, transform_tree, effect_tree))

cc/trees/layer_tree_host_common.cc

@@ -364,10 +364,13 @@ static void ComputeInitialRenderSurfaceList(
     DCHECK(layer);
     // TODO(crbug.com/726423): LayerImpls should never have invalid PropertyTree
     // indices.
-    if (!layer || !layer->HasValidPropertyTreeIndices())
+    if (!layer)
       continue;
-
     layer->set_contributes_to_drawn_render_surface(false);
+    layer->set_raster_even_if_not_drawn(false);
+
+    if (!layer->HasValidPropertyTreeIndices())
+      continue;
 
     bool is_root = layer_tree_impl->IsRootLayer(layer);