cros-md: Remove the non-MD immersive mode code paths

chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h

Index: chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h
diff --git a/chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h b/chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h
index 400aa8bd5a93526e69fad0dd714efe391dc69dea..efaf21654dcec69aad2f304ef6d73764af2dd741 100644
--- a/chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h
+++ b/chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h
@@ -87,11 +87,6 @@ class BrowserNonClientFrameViewAsh : public BrowserNonClientFrameView,
   // strip.
   int GetTabStripRightInset() const;
 
-  // Returns true if we should use a super short header with light bars instead
-  // of regular tabs. This header is used in immersive fullscreen when the
-  // top-of-window views are not revealed.
-  bool UseImmersiveLightbarHeaderStyle() const;
-
   // Returns true if the header should be painted so that it looks the same as
   // the header used for packaged apps. Packaged apps use a different color
   // scheme than browser windows.