Remove WINDOW_TYPE_V1_PANEL AppWindow type

extensions/browser/app_window/app_window.h

Index: extensions/browser/app_window/app_window.h
diff --git a/extensions/browser/app_window/app_window.h b/extensions/browser/app_window/app_window.h
index 72d3090fdef64ccfd60a5ccc7d0e9e9637796312..a850d7137c0ff293eba7e93f14ee1537946a7778 100644
--- a/extensions/browser/app_window/app_window.h
+++ b/extensions/browser/app_window/app_window.h
@@ -94,8 +94,6 @@ class AppWindow : public content::WebContentsDelegate,
   enum WindowType {
     WINDOW_TYPE_DEFAULT = 1 << 0,   // Default app window.
     WINDOW_TYPE_PANEL = 1 << 1,     // OS controlled panel window (Ash only).
-    WINDOW_TYPE_V1_PANEL = 1 << 2,  // For apps v1 support in Ash; deprecate
-                                    // with v1 apps.
   };
 
   enum Frame {
@@ -235,8 +233,7 @@ class AppWindow : public content::WebContentsDelegate,
   content::WebContents* web_contents() const;
   WindowType window_type() const { return window_type_; }
   bool window_type_is_panel() const {
-    return (window_type_ == WINDOW_TYPE_PANEL ||
-            window_type_ == WINDOW_TYPE_V1_PANEL);
+    return window_type_ == WINDOW_TYPE_PANEL;
   }
   content::BrowserContext* browser_context() const { return browser_context_; }
   const gfx::Image& app_icon() const { return app_icon_; }