move window_types.h from ui/wm/public to ui/aura/client

aura uses one file in ui/wm/public: window_types.h. By moving it onto
ui/aura/client, then aura should no longer depend upon ui/wm or build it.

At that point ui/wm can become it's own build target. Which will be done
in the next patch.

BUG=654078
TBR=jochen@chromium.org,reveman@chromium.org

Change-Id: I231964a6eda7078b82ad777fd6fd955a81858a33
Reviewed-on: https://chromium-review.googlesource.com/513947
Reviewed-by: Thiago Farina <tfarina@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Thiago Farina <tfarina@chromium.org>
Cr-Commit-Position: refs/heads/master@{#474552}

diff --git a/ui/aura/BUILD.gn b/ui/aura/BUILD.gn
index 07c0be6..e36d8c6 100644
--- a/ui/aura/BUILD.gn
+++ b/ui/aura/BUILD.gn

@@ -15,7 +15,6 @@
     "../wm/public/scoped_tooltip_disabler.h",
     "../wm/public/tooltip_client.h",
     "../wm/public/window_move_client.h",
-    "../wm/public/window_types.h",
     "client/aura_constants.h",
     "client/capture_client.h",
     "client/capture_client_observer.h",
@@ -34,6 +33,7 @@
     "client/visibility_client.h",
     "client/window_parenting_client.h",
     "client/window_stacking_client.h",
+    "client/window_types.h",
     "env.h",
     "env_input_state_controller.h",
     "env_observer.h",