Remove legacy InfoBarViewProtocol.

ios/chrome/browser/infobars/infobar_controller.mm

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ios/chrome/browser/infobars/infobar_controller.h"
 
 #include <memory>
 
 #include "base/logging.h"
-#import "ios/chrome/browser/ui/infobars/infobar_view_protocol.h"
+#import "ios/chrome/browser/ui/infobars/infobar_view.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 @interface InfoBarController () {
-  UIView<InfoBarViewProtocol>* _infoBarView;
+  InfoBarView* _infoBarView;
 }
 @end
 
 @implementation InfoBarController
 @synthesize delegate = _delegate;
 
 - (instancetype)initWithDelegate:(InfoBarViewDelegate*)delegate {
   self = [super init];
   if (self) {
     DCHECK(delegate);
@@ skipping 14 matching lines @@
 - (int)barHeight {
   return CGRectGetHeight([_infoBarView frame]);
 }
 
 - (void)layoutForDelegate:(infobars::InfoBarDelegate*)delegate
                     frame:(CGRect)bounds {
   DCHECK(!_infoBarView);
   _infoBarView = [self viewForDelegate:delegate frame:bounds];
 }
 
-- (UIView<InfoBarViewProtocol>*)viewForDelegate:
-                                    (infobars::InfoBarDelegate*)delegate
-                                          frame:(CGRect)bounds {
+- (InfoBarView*)viewForDelegate:(infobars::InfoBarDelegate*)delegate
+                          frame:(CGRect)bounds {
   // Must be overriden in subclasses.
   NOTREACHED();
   return _infoBarView;
 }
 
 - (void)onHeightsRecalculated:(int)newHeight {
   [_infoBarView setVisibleHeight:newHeight];
 }
 
-- (UIView<InfoBarViewProtocol>*)view {
+- (InfoBarView*)view {
   return _infoBarView;
 }
 
 - (void)removeView {
   [_infoBarView removeFromSuperview];
 }
 
 - (void)detachView {
   [_infoBarView resetDelegate];
   _delegate = nullptr;
 }
 
 @end