ash/immersive mode: Hide the launcher when entering immersive mode

ash/wm/workspace/workspace.h

Index: ash/wm/workspace/workspace.h
diff --git a/ash/wm/workspace/workspace.h b/ash/wm/workspace/workspace.h
index 575a3683ebda79af79e6c9883d96c9689fbff914..b94f59510946f1df5aded00e342d74a2caf1060b 100644
--- a/ash/wm/workspace/workspace.h
+++ b/ash/wm/workspace/workspace.h
@@ -63,6 +63,11 @@ class ASH_EXPORT Workspace {
   // would be maximized on restore). This does not consider visibility.
   int GetNumMaximizedWindows() const;
 
+  // Returns true if any window in the workspace is in immersive mode. Merely
+  // checking the active window is not sufficient, as the active window may be
+  // a dialog, panel, etc.
+  bool IsImmersiveMode() const;
+
  private:
   // Is this a workspace for maximized windows?
   const bool is_maximized_;