[ios] Remove IDC_BACK and IDC_FORWARD

ios/chrome/browser/ui/toolbar/toolbar_controller.h

Index: ios/chrome/browser/ui/toolbar/toolbar_controller.h
diff --git a/ios/chrome/browser/ui/toolbar/toolbar_controller.h b/ios/chrome/browser/ui/toolbar/toolbar_controller.h
index fd9c3889a4b1f572b89f90e29fea2817647a5f3c..0d15ce45b17ebad421fb8b8b6b56d44e2778d71b 100644
--- a/ios/chrome/browser/ui/toolbar/toolbar_controller.h
+++ b/ios/chrome/browser/ui/toolbar/toolbar_controller.h
@@ -18,6 +18,7 @@
 #include "ios/chrome/browser/ui/ui_util.h"
 #import "ios/chrome/browser/ui/util/relaxed_bounds_constraints_hittest.h"
 
+@protocol BrowserCommands;
 class ReadingListModel;
 @class ToolsMenuConfiguration;
 
@@ -134,6 +135,8 @@ extern const CGRect kToolbarFrame[INTERFACE_IDIOM_COUNT];
 // The reading list model reflected by the toolbar.
 @property(nonatomic, readwrite, assign) ReadingListModel* readingListModel;
 
+@property(nonatomic, readwrite, weak) id<BrowserCommands> dispatcher;
+
 // Designated initializer.  |style| determines how the toolbar draws itself.
 - (instancetype)initWithStyle:(ToolbarControllerStyle)style
     NS_DESIGNATED_INITIALIZER;