Avoid to change layer type in InkDropHostView::AddInkDropLayer

ui/views/animation/ink_drop_host_view.cc

Index: ui/views/animation/ink_drop_host_view.cc
diff --git a/ui/views/animation/ink_drop_host_view.cc b/ui/views/animation/ink_drop_host_view.cc
index 4d56b362811719b2946030e148d45c7edd21af21..f37e61c59a9e7df25e991c1edba6cf986cc05317 100644
--- a/ui/views/animation/ink_drop_host_view.cc
+++ b/ui/views/animation/ink_drop_host_view.cc
@@ -126,6 +126,7 @@ InkDropHostView::~InkDropHostView() {
 }
 
 void InkDropHostView::AddInkDropLayer(ui::Layer* ink_drop_layer) {
+  DCHECK(!layer() || layer()->type() == ui::LAYER_TEXTURED);

[sky, 2017/02/22 21:29:49]

Please add a comment as to why this expects ui::LAYER_TEXTURED. Do you know that
this may happen? If so, when?

[yiyix, 2017/02/22 23:15:39]

I tried to answer your questions in the description of this cl. Is it more clear
now?

   old_paint_to_layer_ = layer() != nullptr;
   SetPaintToLayer();
   layer()->SetFillsBoundsOpaquely(false);