ui: Cleanup class/struct forward declarations

ios/web/web_state/ui/crw_web_controller.mm

Index: ios/web/web_state/ui/crw_web_controller.mm
diff --git a/ios/web/web_state/ui/crw_web_controller.mm b/ios/web/web_state/ui/crw_web_controller.mm
index a072370364a004fa25513f56f7d74ce3e0f4e0c4..0a1ef8e6760fd07c676a15ee65c53274cce1edf8 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -662,6 +662,10 @@ NSError* WKWebViewErrorWithSource(NSError* error, WKWebViewErrorSource source) {
 - (void)loadCompleteWithSuccess:(BOOL)loadSuccess;
 // Called after URL is finished loading and _loadPhase is set to PAGE_LOADED.
 - (void)didFinishWithURL:(const GURL&)currentURL loadSuccess:(BOOL)loadSuccess;
+// Loads a new URL if the current entry is not from a pushState() navigation.
+// |fromEntry| is the CRWSessionEntry that was the current entry prior to the
+// navigation.
+- (void)finishHistoryNavigationFromEntry:(CRWSessionEntry*)fromEntry;
 // Informs the native controller if web usage is allowed or not.
 - (void)setNativeControllerWebUsageEnabled:(BOOL)webUsageEnabled;
 // Called when web controller receives a new message from the web page.
@@ -1135,6 +1139,8 @@ const NSTimeInterval kSnapshotOverlayTransition = 0.5;
   DCHECK([NSThread isMainThread]);
   DCHECK(_isBeingDestroyed);  // 'close' must have been called already.
   DCHECK(!_webView);
+  // TODO(crbug.com/662860): Don't set the delegate to nil.
+  [_containerView setDelegate:nil];
   _touchTrackingRecognizer.get().touchTrackingDelegate = nil;
   [[_webViewProxy scrollViewProxy] removeObserver:self];
   [[NSNotificationCenter defaultCenter] removeObserver:self];
@@ -5397,13 +5403,16 @@ const NSTimeInterval kSnapshotOverlayTransition = 0.5;
   GURL webViewURL = net::GURLWithNSURL([_webView URL]);
 
   // For failed navigations, WKWebView will sometimes revert to the previous URL
-  // before resettings its |isLoading| property to NO.  If this is the first
-  // navigation for the web view, this will result in an empty URL.
-  if (webViewURL.is_empty() || webViewURL == _documentURL)
+  // before committing the current navigation or resetting the web view's
+  // |isLoading| property to NO.  If this is the first navigation for the web
+  // view, this will result in an empty URL.
+  BOOL navigationWasCommitted = _loadPhase != web::LOAD_REQUESTED;
+  if (!navigationWasCommitted &&
+      (webViewURL.is_empty() || webViewURL == _documentURL)) {
     return;
+  }
 
-  if (_loadPhase == web::LOAD_REQUESTED &&
-      ![_pendingNavigationInfo cancelled]) {
+  if (!navigationWasCommitted && ![_pendingNavigationInfo cancelled]) {
     // A fast back/forward within the same origin does not call
     // |didCommitNavigation:|, so signal page change explicitly.
     DCHECK_EQ(_documentURL.GetOrigin(), webViewURL.GetOrigin());