Revert of [ObjC ARC] Converts crw_web_controller to ARC.

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 300da72f70b26c2a4c96bfb56050819f4f138a1f..3a16eb13445920cfaa8c413a01d9ae1cd561f1c4 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -18,12 +18,14 @@
 #include "base/ios/block_types.h"
 #include "base/ios/ios_util.h"
 #import "base/ios/ns_error_util.h"
+#include "base/ios/weak_nsobject.h"
 #include "base/json/json_reader.h"
 #include "base/json/string_escape.h"
 #include "base/logging.h"
 #include "base/mac/bind_objc_block.h"
 #include "base/mac/bundle_locations.h"
 #include "base/mac/foundation_util.h"
+#include "base/mac/objc_property_releaser.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/metrics/histogram.h"
@@ -105,10 +107,6 @@
 #include "url/gurl.h"
 #include "url/url_constants.h"
 
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
 using base::UserMetricsAction;
 using web::NavigationManager;
 using web::NavigationManagerImpl;
@@ -253,7 +251,10 @@
 // A container object for any navigation information that is only available
 // during pre-commit delegate callbacks, and thus must be held until the
 // navigation commits and the informatino can be used.
-@interface CRWWebControllerPendingNavigationInfo : NSObject
+@interface CRWWebControllerPendingNavigationInfo : NSObject {
+  base::mac::ObjCPropertyReleaser
+      _propertyReleaser_CRWWebControllerPendingNavigationInfo;
+}
 // The referrer for the page.
 @property(nonatomic, copy) NSString* referrer;
 // The MIME type for the page.
@@ -278,6 +279,8 @@
 
 - (instancetype)init {
   if ((self = [super init])) {
+    _propertyReleaser_CRWWebControllerPendingNavigationInfo.Init(
+        self, [CRWWebControllerPendingNavigationInfo class]);
     _navigationType = WKNavigationTypeOther;
   }
   return self;
@@ -291,6 +294,10 @@
                                CRWWebViewScrollViewProxyObserver,
                                WKNavigationDelegate,
                                WKUIDelegate> {
+  base::WeakNSProtocol<id<CRWWebDelegate>> _delegate;
+  base::WeakNSProtocol<id<CRWWebUserInterfaceDelegate>> _UIDelegate;
+  base::WeakNSProtocol<id<CRWNativeContentProvider>> _nativeProvider;
+  base::WeakNSProtocol<id<CRWSwipeRecognizerProvider>> _swipeRecognizerProvider;
   // The WKWebView managed by this instance.
   base::scoped_nsobject<WKWebView> _webView;
   // The CRWWebViewProxy is the wrapper to give components access to the
@@ -449,7 +456,7 @@
   // The WKNavigation captured when |stopLoading| was called. Used for reporting
   // WebController.EmptyNavigationManagerCausedByStopLoading UMA metric which
   // helps with diagnosing a navigation related crash (crbug.com/565457).
-  __weak WKNavigation* _stoppedWKNavigation;
+  base::WeakNSObject<WKNavigation> _stoppedWKNavigation;
 
   // CRWWebUIManager object for loading WebUI pages.
   base::scoped_nsobject<CRWWebUIManager> _webUIManager;
@@ -473,23 +480,26 @@
 
 // If |contentView_| contains a web view, this is the web view it contains.
 // If not, it's nil.
-@property(nonatomic, strong, readonly) WKWebView* webView;
+@property(nonatomic, readonly) WKWebView* webView;
 // The scroll view of |webView|.
-@property(nonatomic, strong, readonly) UIScrollView* webScrollView;
+@property(nonatomic, readonly) UIScrollView* webScrollView;
 // The current page state of the web view. Writing to this property
 // asynchronously applies the passed value to the current web view.
 @property(nonatomic, readwrite) web::PageDisplayState pageDisplayState;
 // The currently displayed native controller, if any.
-@property(nonatomic, strong) id<CRWNativeContent> nativeController;
+@property(nonatomic, readwrite) id<CRWNativeContent> nativeController;
 // Returns NavigationManager's session controller.
-@property(nonatomic, strong, readonly) CRWSessionController* sessionController;
+@property(nonatomic, readonly) CRWSessionController* sessionController;
 // Activity indicator group ID for this web controller.
-@property(nonatomic, copy, readonly) NSString* activityIndicatorGroupID;
-// List of keypaths observed on WKWebView. All KVO-observed keypaths have to
-// be added to this list.
-@property(nonatomic, strong, readonly) NSArray* observedKeyPaths;
+@property(nonatomic, readonly) NSString* activityIndicatorGroupID;
+// Dictionary where keys are the names of WKWebView properties and values are
+// selector names which should be called when a corresponding property has
+// changed. e.g. @{ @"URL" : @"webViewURLDidChange" } means that
+// -[self webViewURLDidChange] must be called every time when WKWebView.URL is
+// changed.
+@property(nonatomic, readonly) NSDictionary* WKWebViewObservers;
 // Downloader for PassKit files. Lazy initialized.
-@property(nonatomic, strong, readonly) CRWPassKitDownloader* passKitDownloader;
+@property(nonatomic, readonly) CRWPassKitDownloader* passKitDownloader;
 
 // The web view's view of the current URL. During page transitions
 // this may not be the same as the session history's view of the current URL.
@@ -1018,10 +1028,6 @@
 @synthesize usePlaceholderOverlay = _usePlaceholderOverlay;
 @synthesize loadPhase = _loadPhase;
 @synthesize shouldSuppressDialogs = _shouldSuppressDialogs;
-@synthesize delegate = _delegate;
-@synthesize UIDelegate = _UIDelegate;
-@synthesize nativeProvider = _nativeProvider;
-@synthesize swipeRecognizerProvider = _swipeRecognizerProvider;
 
 - (instancetype)initWithWebState:(WebStateImpl*)webState {
   self = [super init];
@@ -1056,6 +1062,23 @@
   return self;
 }
 
+- (id<CRWNativeContentProvider>)nativeProvider {
+  return _nativeProvider.get();
+}
+
+- (void)setNativeProvider:(id<CRWNativeContentProvider>)nativeProvider {
+  _nativeProvider.reset(nativeProvider);
+}
+
+- (id<CRWSwipeRecognizerProvider>)swipeRecognizerProvider {
+  return _swipeRecognizerProvider.get();
+}
+
+- (void)setSwipeRecognizerProvider:
+    (id<CRWSwipeRecognizerProvider>)swipeRecognizerProvider {
+  _swipeRecognizerProvider.reset(swipeRecognizerProvider);
+}
+
 - (WebState*)webState {
   return _webStateImpl;
 }
@@ -1086,15 +1109,26 @@
   [_containerView displayTransientContent:contentView];
 }
 
+- (id<CRWWebDelegate>)delegate {
+  return _delegate.get();
+}
 
 - (void)setDelegate:(id<CRWWebDelegate>)delegate {
-  _delegate = delegate;
+  _delegate.reset(delegate);
   if ([self.nativeController respondsToSelector:@selector(setDelegate:)]) {
     if ([_delegate respondsToSelector:@selector(webController:titleDidChange:)])
       [self.nativeController setDelegate:self];
     else
       [self.nativeController setDelegate:nil];
   }
+}
+
+- (id<CRWWebUserInterfaceDelegate>)UIDelegate {
+  return _UIDelegate.get();
+}
+
+- (void)setUIDelegate:(id<CRWWebUserInterfaceDelegate>)UIDelegate {
+  _UIDelegate.reset(UIDelegate);
 }
 
 - (void)dealloc {
@@ -1105,6 +1139,7 @@
   _touchTrackingRecognizer.get().touchTrackingDelegate = nil;
   [[_webViewProxy scrollViewProxy] removeObserver:self];
   [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [super dealloc];
 }
 
 - (void)dismissKeyboard {
@@ -1136,11 +1171,15 @@
                        self.webStateImpl->GetRequestGroupID()];
 }
 
-- (NSArray*)observedKeyPaths {
-  return @[
-    @"certificateChain", @"estimatedProgress", @"hasOnlySecureContent",
-    @"loading", @"title", @"URL"
-  ];
+- (NSDictionary*)WKWebViewObservers {
+  return @{
+    @"certificateChain" : @"webViewSecurityFeaturesDidChange",
+    @"estimatedProgress" : @"webViewEstimatedProgressDidChange",
+    @"hasOnlySecureContent" : @"webViewSecurityFeaturesDidChange",
+    @"loading" : @"webViewLoadingStateDidChange",
+    @"title" : @"webViewTitleDidChange",
+    @"URL" : @"webViewURLDidChange",
+  };
 }
 
 // NativeControllerDelegate method, called to inform that title has changed.
@@ -1286,7 +1325,7 @@
 
   web::ContextMenuParams params =
       [self contextMenuParamsForElement:_DOMElementForLastTouch.get()];
-  params.view.reset(_webView);
+  params.view.reset([_webView retain]);
   params.location = [gestureRecognizer locationInView:_webView];
   if (self.webStateImpl->HandleContextMenu(params)) {
     // Cancelling all touches has the intended side effect of suppressing the
@@ -1329,7 +1368,8 @@
     UIImage* result = UIGraphicsGetImageFromCurrentImageContext();
     UIGraphicsEndImageContext();
 
-    defaultImage = [result stretchableImageWithLeftCapWidth:1 topCapHeight:1];
+    defaultImage =
+        [[result stretchableImageWithLeftCapWidth:1 topCapHeight:1] retain];
   }
   return defaultImage;
 }
@@ -1567,7 +1607,7 @@
         // that the lifetimes work out.
         // Note that normally using the value as the key wouldn't make any
         // sense, but here it's fine since nothing needs to look up the value.
-        objc_setAssociatedObject(view, (__bridge void*)recognizer, recognizer,
+        objc_setAssociatedObject(view, recognizer, recognizer,
                                  OBJC_ASSOCIATION_RETAIN_NONATOMIC);
       }
     }
@@ -1779,12 +1819,12 @@
     [script appendString:[self javaScriptToDispatchHashChangeWithOldURL:oldURL
                                                                  newURL:URL]];
   }
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   [self executeJavaScript:script
         completionHandler:^(id, NSError*) {
-          base::scoped_nsobject<CRWWebController> strongSelf(weakSelf);
-          if (!strongSelf || strongSelf.get()->_isBeingDestroyed)
+          if (!weakSelf || weakSelf.get()->_isBeingDestroyed)
             return;
+          base::scoped_nsobject<CRWWebController> strongSelf([weakSelf retain]);
           strongSelf.get()->_URLOnStartLoading = URL;
           strongSelf.get()->_lastRegisteredRequestURL = URL;
         }];
@@ -2265,7 +2305,7 @@
   // fromEntry is retained because it has the potential to be released
   // by goDelta: if it has not been committed.
   base::scoped_nsobject<CRWSessionEntry> fromEntry(
-      [sessionController currentEntry]);
+      [[sessionController currentEntry] retain]);
   [sessionController goDelta:delta];
   if (fromEntry) {
     [self finishHistoryNavigationFromEntry:fromEntry];
@@ -2460,9 +2500,9 @@
   if (_passKitDownloader) {
     return _passKitDownloader.get();
   }
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   web::PassKitCompletionHandler passKitCompletion = ^(NSData* data) {
-    base::scoped_nsobject<CRWWebController> strongSelf(weakSelf);
+    base::scoped_nsobject<CRWWebController> strongSelf([weakSelf retain]);
     if (!strongSelf) {
       return;
     }
@@ -3079,18 +3119,16 @@
 
   NSString* replaceWebViewJS =
       [self javaScriptToReplaceWebViewURL:pushURL stateObjectJSON:stateObject];
-  __weak CRWWebController* weakSelf = self;
-  [self executeJavaScript:replaceWebViewJS
-        completionHandler:^(id, NSError*) {
-          base::scoped_nsobject<CRWWebController> strongSelf(weakSelf);
-          if (!strongSelf || strongSelf.get()->_isBeingDestroyed)
-            return;
-          [strongSelf optOutScrollsToTopForSubviews];
-          // Notify the observers.
-          strongSelf.get()->_webStateImpl->OnHistoryStateChanged();
-          [strongSelf didFinishNavigation];
-        }];
-
+  base::WeakNSObject<CRWWebController> weakSelf(self);
+  [self executeJavaScript:replaceWebViewJS completionHandler:^(id, NSError*) {
+    if (!weakSelf || weakSelf.get()->_isBeingDestroyed)
+      return;
+    base::scoped_nsobject<CRWWebController> strongSelf([weakSelf retain]);
+    [strongSelf optOutScrollsToTopForSubviews];
+    // Notify the observers.
+    strongSelf.get()->_webStateImpl->OnHistoryStateChanged();
+    [strongSelf didFinishNavigation];
+  }];
   return YES;
 }
 
@@ -3140,14 +3178,13 @@
   [self replaceStateWithPageURL:replaceURL stateObject:stateObject];
   NSString* replaceStateJS = [self javaScriptToReplaceWebViewURL:replaceURL
                                                  stateObjectJSON:stateObject];
-  __weak CRWWebController* weakSelf = self;
-  [self executeJavaScript:replaceStateJS
-        completionHandler:^(id, NSError*) {
-          base::scoped_nsobject<CRWWebController> strongSelf(weakSelf);
-          if (!strongSelf || strongSelf.get()->_isBeingDestroyed)
-            return;
-          [strongSelf didFinishNavigation];
-        }];
+  base::WeakNSObject<CRWWebController> weakSelf(self);
+  [self executeJavaScript:replaceStateJS completionHandler:^(id, NSError*) {
+    if (!weakSelf || weakSelf.get()->_isBeingDestroyed)
+      return;
+    base::scoped_nsobject<CRWWebController> strongSelf([weakSelf retain]);
+    [strongSelf didFinishNavigation];
+  }];
   return YES;
 }
 
@@ -3563,7 +3600,7 @@
   // menu and show another one. If for some reason context menu info is not
   // fetched - system context menu will be shown.
   [self setDOMElementForLastTouch:nil];
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   [self fetchDOMElementAtPoint:[touch locationInView:_webView]
              completionHandler:^(NSDictionary* element) {
                [weakSelf setDOMElementForLastTouch:element];
@@ -3678,7 +3715,7 @@
   const GURL currentURL([self currentNavigationURL]);
   NSString* windowName = windowInfo.window_name.get();
   web::Referrer referrer(currentURL, windowInfo.referrer_policy);
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   void (^showPopupHandler)() = ^{
     CRWWebController* child = [[weakSelf delegate] webPageOrderedOpen:url
                                                              referrer:referrer
@@ -3993,12 +4030,12 @@
         (CRWWebViewScrollViewProxy*)webViewScrollViewProxy {
   _pageHasZoomed = YES;
 
-  __weak UIScrollView* weakScrollView = self.webScrollView;
+  base::WeakNSObject<UIScrollView> weakScrollView(self.webScrollView);
   [self extractViewportTagWithCompletion:^(
             const web::PageViewportState* viewportState) {
     if (!weakScrollView)
       return;
-    base::scoped_nsobject<UIScrollView> scrollView(weakScrollView);
+    base::scoped_nsobject<UIScrollView> scrollView([weakScrollView retain]);
     if (viewportState && !viewportState->viewport_tag_present() &&
         [scrollView minimumZoomScale] == [scrollView maximumZoomScale] &&
         [scrollView zoomScale] > 1.0) {
@@ -4113,7 +4150,7 @@
   NSString* const kViewportContentQuery =
       @"var viewport = document.querySelector('meta[name=\"viewport\"]');"
        "viewport ? viewport.content : '';";
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   int itemID = currentItem->GetUniqueID();
   [self executeJavaScript:kViewportContentQuery
         completionHandler:^(id viewportContent, NSError*) {
@@ -4162,7 +4199,7 @@
 - (void)applyPageDisplayState:(const web::PageDisplayState&)displayState {
   if (!displayState.IsValid())
     return;
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   web::PageDisplayState displayStateCopy = displayState;
   [self extractViewportTagWithCompletion:^(
             const web::PageViewportState* viewportState) {
@@ -4251,7 +4288,7 @@
   } else {
     // If the page isn't loaded, store the action to update the scroll
     // when the page finishes loading.
-    __weak UIScrollView* weakScrollView = self.webScrollView;
+    base::WeakNSObject<UIScrollView> weakScrollView(self.webScrollView);
     base::scoped_nsprotocol<ProceduralBlock> action([^{
       [weakScrollView setContentOffset:scrollOffset];
     } copy]);
@@ -4281,7 +4318,7 @@
   // scrolled).
   CGPoint scrollOffset = self.scrollPosition;
   CGFloat webViewContentWidth = self.webScrollView.contentSize.width;
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   [self fetchWebPageWidthWithCompletionHandler:^(CGFloat pageWidth) {
     CGFloat scale = pageWidth / webViewContentWidth;
     CGPoint localPoint = CGPointMake((point.x + scrollOffset.x) * scale,
@@ -4313,7 +4350,7 @@
   if (src) {
     params.src_url = GURL(base::SysNSStringToUTF8(src));
     if (!title)
-      title = [src copy];
+      title = [[src copy] autorelease];
     if ([title hasPrefix:base::SysUTF8ToNSString(url::kDataScheme)])
       title = nil;
   }
@@ -4388,7 +4425,7 @@
       web::ReferrerPolicyFromString(referrerPolicyString);
   web::Referrer referrer(sourceURL, referrerPolicy);
   NSString* const kWindowName = @"";  // obsoleted
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   void (^showPopupHandler)() = ^{
     // On Desktop cross-window comunication is not supported for unblocked
     // popups; so it's ok to create a new independent page.
@@ -4406,7 +4443,7 @@
 
 - (void)didBlockPopupWithURL:(GURL)popupURL sourceURL:(GURL)sourceURL {
   if ([_delegate respondsToSelector:@selector(webController:didBlockPopup:)]) {
-    __weak CRWWebController* weakSelf = self;
+    base::WeakNSObject<CRWWebController> weakSelf(self);
     dispatch_async(dispatch_get_main_queue(), ^{
       [self queryPageReferrerPolicy:^(NSString* policy) {
         [weakSelf didBlockPopupWithURL:popupURL
@@ -4672,9 +4709,9 @@
 }
 
 - (WKWebView*)createWebViewWithConfiguration:(WKWebViewConfiguration*)config {
-  return web::CreateWKWebView(CGRectZero, config,
-                              self.webStateImpl->GetBrowserState(),
-                              [self useDesktopUserAgent]);
+  return [web::CreateWKWebView(CGRectZero, config,
+                               self.webStateImpl->GetBrowserState(),
+                               [self useDesktopUserAgent]) autorelease];
 }
 
 - (void)setWebView:(WKWebView*)webView {
@@ -4690,16 +4727,16 @@
   }
   [_webView setNavigationDelegate:nil];
   [_webView setUIDelegate:nil];
-  for (NSString* keyPath in self.observedKeyPaths) {
+  for (NSString* keyPath in self.WKWebViewObservers) {
     [_webView removeObserver:self forKeyPath:keyPath];
   }
   [self clearActivityIndicatorTasks];
 
-  _webView.reset(webView);
+  _webView.reset([webView retain]);
 
   // Set up the new web view.
   if (webView) {
-    __weak CRWWebController* weakSelf = self;
+    base::WeakNSObject<CRWWebController> weakSelf(self);
     [messageRouter setScriptMessageHandler:^(WKScriptMessage* message) {
       [weakSelf didReceiveScriptMessage:message];
     }
@@ -4712,7 +4749,7 @@
   }
   [_webView setNavigationDelegate:self];
   [_webView setUIDelegate:self];
-  for (NSString* keyPath in self.observedKeyPaths) {
+  for (NSString* keyPath in self.WKWebViewObservers) {
     [_webView addObserver:self forKeyPath:keyPath options:0 context:nullptr];
   }
   _injectedScriptManagers.reset([[NSMutableSet alloc] init]);
@@ -4768,7 +4805,7 @@
 }
 
 - (void)loadRequest:(NSMutableURLRequest*)request {
-  _latestWKNavigation.reset([_webView loadRequest:request]);
+  _latestWKNavigation.reset([[_webView loadRequest:request] retain]);
 }
 
 - (void)loadPOSTRequest:(NSMutableURLRequest*)request {
@@ -4814,7 +4851,7 @@
 }
 
 - (void)stopLoading {
-  _stoppedWKNavigation = _latestWKNavigation;
+  _stoppedWKNavigation.reset(_latestWKNavigation);
 
   base::RecordAction(UserMetricsAction("Stop"));
   // Discard the pending and transient entried before notifying the tab model
@@ -5111,7 +5148,7 @@
   // Ensure the URL is registered and loadPhase is as expected.
   DCHECK(_lastRegisteredRequestURL == webViewURL);
   DCHECK(self.loadPhase == web::LOAD_REQUESTED);
-  _latestWKNavigation.reset(navigation);
+  _latestWKNavigation.reset([navigation retain]);
 }
 
 - (void)webView:(WKWebView*)webView
@@ -5260,13 +5297,14 @@
   SecTrustRef trust = challenge.protectionSpace.serverTrust;
   base::ScopedCFTypeRef<SecTrustRef> scopedTrust(trust,
                                                  base::scoped_policy::RETAIN);
-  __weak CRWWebController* weakSelf = self;
+  base::WeakNSObject<CRWWebController> weakSelf(self);
   [_certVerificationController
       decideLoadPolicyForTrust:scopedTrust
                           host:challenge.protectionSpace.host
              completionHandler:^(web::CertAcceptPolicy policy,
                                  net::CertStatus status) {
-               base::scoped_nsobject<CRWWebController> strongSelf(weakSelf);
+               base::scoped_nsobject<CRWWebController> strongSelf(
+                   [weakSelf retain]);
                if (!strongSelf) {
                  completionHandler(
                      NSURLSessionAuthChallengeRejectProtectionSpace, nil);
@@ -5312,23 +5350,10 @@
                       ofObject:(id)object
                         change:(NSDictionary*)change
                        context:(void*)context {
-  // All observed keypaths have to be present in |self.observedKeyPaths|.
-  DCHECK([self.observedKeyPaths containsObject:keyPath]);
-  if ([keyPath isEqualToString:@"certificateChain"]) {
-    [self webViewSecurityFeaturesDidChange];
-  } else if ([keyPath isEqualToString:@"estimatedProgress"]) {
-    [self webViewEstimatedProgressDidChange];
-  } else if ([keyPath isEqualToString:@"hasOnlySecureContent"]) {
-    [self webViewSecurityFeaturesDidChange];
-  } else if ([keyPath isEqualToString:@"loading"]) {
-    [self webViewLoadingStateDidChange];
-  } else if ([keyPath isEqualToString:@"title"]) {
-    [self webViewTitleDidChange];
-  } else if ([keyPath isEqualToString:@"URL"]) {
-    [self webViewURLDidChange];
-  } else {
-    NOTREACHED();
-  }
+  NSString* dispatcherSelectorName = self.WKWebViewObservers[keyPath];
+  DCHECK(dispatcherSelectorName);
+  if (dispatcherSelectorName)
+    [self performSelector:NSSelectorFromString(dispatcherSelectorName)];
 }
 
 - (void)webViewEstimatedProgressDidChange {