Converts most of WorkspaceLayoutManager tests to use common code

ash/common/wm_window.h

Index: ash/common/wm_window.h
diff --git a/ash/common/wm_window.h b/ash/common/wm_window.h
index a02cbf743d5aedbe69a52dc5c9e9c1f590620ea4..441126b2cf1bea90120b53d73e136c1b0f15f6fd 100644
--- a/ash/common/wm_window.h
+++ b/ash/common/wm_window.h
@@ -94,9 +94,12 @@ class ASH_EXPORT WmWindow {
 
   virtual bool IsBubble() = 0;
 
-  // TODO(sky): seems like this shouldn't be exposed.
   virtual ui::Layer* GetLayer() = 0;
 
+  // TODO(sky): these are temporary until GetLayer() always returns non-null.
+  virtual bool GetLayerTargetVisibility() = 0;
+  virtual bool GetLayerVisible() = 0;
+
   virtual display::Display GetDisplayNearestWindow() = 0;
 
   virtual bool HasNonClientArea() = 0;
@@ -238,6 +241,8 @@ class ASH_EXPORT WmWindow {
 
   virtual bool HasRestoreBounds() const = 0;
 
+  virtual void SetPinned(bool trusted) = 0;

[James Cook, 2016/10/04 23:16:04]

Function docs? (I actually don't know what pinned means.)

[sky, 2016/10/06 17:57:07]

Done.

+
   virtual void SetAlwaysOnTop(bool value) = 0;
   virtual bool IsAlwaysOnTop() const = 0;