Remove a bunch of pre-MD toolbar code and assets.

chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h

Index: chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h
diff --git a/chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h b/chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h
index 380de464b81869b998b3a9b5b4043f801fdd7b7b..bc4ef6894e4772e6c23def8777c6944be04aa079 100644
--- a/chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h
+++ b/chrome/browser/ui/cocoa/toolbar/app_toolbar_button.h
@@ -11,19 +11,15 @@
 
 #import "chrome/browser/ui/cocoa/menu_button.h"
 #include "chrome/browser/ui/toolbar/app_menu_icon_controller.h"
-#include "chrome/browser/ui/toolbar/app_menu_icon_painter.h"
-
-class AppMenuButtonIconPainterDelegateMac;
 
 // Button for the app toolbar button.
 @interface AppToolbarButton : MenuButton {
  @private
-  std::unique_ptr<AppMenuButtonIconPainterDelegateMac> delegate_;
-  AppMenuIconPainter::Severity severity_;
+  AppMenuIconController::Severity severity_;
   AppMenuIconController::IconType type_;
 }
 
-- (void)setSeverity:(AppMenuIconPainter::Severity)severity
+- (void)setSeverity:(AppMenuIconController::Severity)severity
            iconType:(AppMenuIconController::IconType)iconType
       shouldAnimate:(BOOL)shouldAnimate;