Removed _lastSeenWindowID ivar from CRWWebController as unused.

ios/web/web_state/ui/crw_web_controller.mm

 // Copyright 2012 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/web_state/ui/crw_web_controller.h"
 
 #import <WebKit/WebKit.h>
 
 #import <objc/runtime.h>
 #include <stddef.h>
@@ skipping 307 matching lines @@
   BOOL _isHalted;  // YES if halted. Halting happens prior to destruction.
   BOOL _isBeingDestroyed;  // YES if in the process of closing.
   // All CRWWebControllerObservers attached to the CRWWebController. A
   // specially-constructed set is used that does not retain its elements.
   base::scoped_nsobject<NSMutableSet> _observers;
   // Each observer in |_observers| is associated with a
   // WebControllerObserverBridge in order to listen from WebState callbacks.
   // TODO(droger): Remove |_observerBridges| when all CRWWebControllerObservers
   // are converted to WebStateObservers.
   ScopedVector<web::WebControllerObserverBridge> _observerBridges;
-  // |windowId| that is saved when a page changes. Used to detect refreshes.
-  base::scoped_nsobject<NSString> _lastSeenWindowID;
   // YES if a user interaction has been registered at any time once the page has
   // loaded.
   BOOL _userInteractionRegistered;
   // YES if the user has interacted with the content area since the last URL
   // change.
   BOOL _interactionRegisteredSinceLastURLChange;
   // The actual URL of the document object (i.e., the last committed URL).
   // TODO(crbug.com/549616): Remove this in favor of just updating the
   // navigation manager and treating that as authoritative.
   GURL _documentURL;
@@ skipping 693 matching lines @@
     _webStateImpl->InitializeRequestTracker(self);
     // Load phase when no WebView present is 'loaded' because this represents
     // the idle state.
     _loadPhase = web::PAGE_LOADED;
     // Content area is lazily instantiated.
     _defaultURL = GURL(url::kAboutBlankURL);
     _jsInjectionReceiver.reset(
         [[CRWJSInjectionReceiver alloc] initWithEvaluator:self]);
     _windowIDJSManager.reset([(CRWJSWindowIdManager*)[_jsInjectionReceiver
         instanceOfClass:[CRWJSWindowIdManager class]] retain]);
-    _lastSeenWindowID.reset();
     _webViewProxy.reset(
         [[CRWWebViewProxyImpl alloc] initWithWebController:self]);
     [[_webViewProxy scrollViewProxy] addObserver:self];
     _gestureRecognizers.reset([[NSMutableArray alloc] init]);
     _webViewToolbars.reset([[NSMutableArray alloc] init]);
     _pendingLoadCompleteActions.reset([[NSMutableArray alloc] init]);
     web::BrowserState* browserState = _webStateImpl->GetBrowserState();
     _certVerificationController.reset([[CRWCertVerificationController alloc]
         initWithBrowserState:browserState]);
     _certVerificationErrors.reset(
@@ skipping 2143 matching lines @@
   // TODO(stuartmorgan): This shouldn't be called for hash state or
   // push/replaceState.
   [self resetDocumentSpecificState];
 
   [self didStartLoadingURL:currentURL updateHistory:YES];
 }
 
 - (void)resetDocumentSpecificState {
   _lastUserInteraction.reset();
   _clickInProgress = NO;
-  _lastSeenWindowID.reset([[_windowIDJSManager windowId] copy]);
 }
 
 - (void)didStartLoadingURL:(const GURL&)url updateHistory:(BOOL)updateHistory {
   _loadPhase = web::PAGE_LOADING;
   _URLOnStartLoading = url;
   _displayStateOnStartLoading = self.pageDisplayState;
 
   self.userInteractionRegistered = NO;
   _pageHasZoomed = NO;
 
@@ skipping 2432 matching lines @@
   }
 
   return web::WEB_VIEW_DOCUMENT_TYPE_GENERIC;
 }
 
 - (NSString*)refererFromNavigationAction:(WKNavigationAction*)action {
   return [action.request valueForHTTPHeaderField:@"Referer"];
 }
 
 @end