DRAFT: Add setKeyboardVisibility API.

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 67551c8440ba896b75d038d59c41aab8768a7314..246fa8978da9de071fdca034da1eed2ef397292e 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -48,6 +48,9 @@ class ImageSkia;
 class Point;
 class Rect;
 }
+namespace keyboard {
+class KeyboardController;
+}
 namespace ui {
 class Layer;
 }
@@ -197,6 +200,9 @@ class ASH_EXPORT Shell
       int container_id,
       aura::RootWindow* priority_root);
 
+  // Returns the KeyboardController, or NULL if there is no KeyboardController.
+  static keyboard::KeyboardController* GetKeyboardController();
+
   // True if "launcher per display" feature  is enabled.
   static bool IsLauncherPerDisplayEnabled();