[Mac] Convert Omnibox paste-and-go to use AutocompleteTextFieldObserver.

chrome/browser/cocoa/autocomplete_text_field_editor.h

 // Copyright (c) 2009 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 <Cocoa/Cocoa.h>
 
 class AutocompleteTextFieldObserver;
 
 // AutocompleteTextFieldEditor customized the AutocompletTextField
 // field editor (helper text-view used in editing).  It intercepts UI
 // events for forwarding to the core Omnibox code.  It also undoes
 // some of the effects of using styled text in the Omnibox (the text
 // is styled but should not appear that way when copied to the
 // pasteboard).
 
-// TODO(shess): Move delegate stuff to AutocompleteTextFieldObserver.
-
-@protocol AutocompleteTextFieldEditorDelegateMethods
-
-// Returns nil if paste actions are not supported.
-- (NSString*)textPasteActionString:(NSText*)fieldEditor;
-- (void)textDidPasteAndGo:(NSText*)fieldEditor;
-@end
-
 // Field editor used for the autocomplete field.
 @interface AutocompleteTextFieldEditor : NSTextView {
 }
 
 // Copy contents of the TextView to the designated clipboard as plain
 // text.
 - (void)performCopy:(NSPasteboard*)pb;
 
 // Same as above, note that this calls through to performCopy.
 - (void)performCut:(NSPasteboard*)pb;
 
 @end
 
 @interface AutocompleteTextFieldEditor(PrivateTestMethods)
 - (AutocompleteTextFieldObserver*)observer;
+- (void)pasteAndGo:sender;
 @end