Move delegate imports to implementation file.

ios/web_view/shell/shell_view_controller.m

 // Copyright 2014 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.
 
 #import "ios/web_view/shell/shell_view_controller.h"
 
 #import <MobileCoreServices/MobileCoreServices.h>
 
 #import "ios/web_view/public/cwv.h"
 #import "ios/web_view/public/cwv_html_element.h"
+#import "ios/web_view/public/cwv_navigation_delegate.h"
+#import "ios/web_view/public/cwv_ui_delegate.h"
 #import "ios/web_view/public/cwv_web_view.h"
 #import "ios/web_view/shell/translate_controller.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 // Externed accessibility identifier.
 NSString* const kWebViewShellBackButtonAccessibilityLabel = @"Back";
 NSString* const kWebViewShellForwardButtonAccessibilityLabel = @"Forward";
@@ skipping 311 matching lines @@
   // TODO(crbug.com/679895): Add some visual indication that the page load has
   // finished.
   [self updateToolbar];
 }
 
 - (void)webViewWebContentProcessDidTerminate:(CWVWebView*)webView {
   NSLog(@"webViewWebContentProcessDidTerminate");
 }
 
 @end