Updated the VK Tray button to properly remove visual activated state.

ash/shell_observer.h

Index: ash/shell_observer.h
diff --git a/ash/shell_observer.h b/ash/shell_observer.h
index 5937bb2bf0441489338daed8fc2d8f9d3349c355..c76ede7013547fb59a83bc9083d048173fe153f5 100644
--- a/ash/shell_observer.h
+++ b/ash/shell_observer.h
@@ -63,6 +63,9 @@ class ASH_EXPORT ShellObserver {
   virtual void OnVirtualKeyboardStateChanged(bool activated,
                                              aura::Window* root_window) {}
 
+  // Called when a new KeyboardController is created.
+  virtual void OnKeyboardControllerCreated() {}
+
   // Called at the end of Shell::Init.
   virtual void OnShellInitialized() {}