Return WKNavigation from loadRequest and loadPostRequest.

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 b87fdca8210473345a426bd70ff40bb71fa3feaf..1e7c47326955a1b846d668542693cd7c5a13dfed 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -563,7 +563,7 @@ NSError* WKWebViewErrorWithSource(NSError* error, WKWebViewErrorSource source) {
 // Returns |YES| if |url| should be loaded in a native view.
 - (BOOL)shouldLoadURLInNativeView:(const GURL&)url;
 // Loads the request into the |webView|.
-- (void)loadRequest:(NSMutableURLRequest*)request;
+- (WKNavigation*)loadRequest:(NSMutableURLRequest*)request;
 // Loads POST request with body in |_wkWebView| by constructing an HTML page
 // that executes the request through JavaScript and replaces document with the
 // result.
@@ -571,7 +571,7 @@ NSError* WKWebViewErrorWithSource(NSError* error, WKWebViewErrorSource source) {
 // the data is passed to |_wkWebView| on main thread.
 // This is necessary because WKWebView ignores POST request body.
 // Workaround for https://bugs.webkit.org/show_bug.cgi?id=145410
-- (void)loadPOSTRequest:(NSMutableURLRequest*)request;
+- (WKNavigation*)loadPOSTRequest:(NSMutableURLRequest*)request;
 // Loads the HTML into the page at the given URL.
 - (void)loadHTML:(NSString*)html forURL:(const GURL&)url;
 
@@ -4043,12 +4043,14 @@ const NSTimeInterval kSnapshotOverlayTransition = 0.5;
   return web::WKWebViewConfigurationProvider::FromBrowserState(browserState);
 }
 
-- (void)loadRequest:(NSMutableURLRequest*)request {
+- (WKNavigation*)loadRequest:(NSMutableURLRequest*)request {
+  WKNavigation* navigation = [_webView loadRequest:request];
   [_navigationStates setState:web::WKNavigationState::REQUESTED
-                forNavigation:[_webView loadRequest:request]];
+                forNavigation:navigation];
+  return navigation;
 }
 
-- (void)loadPOSTRequest:(NSMutableURLRequest*)request {
+- (WKNavigation*)loadPOSTRequest:(NSMutableURLRequest*)request {
   if (!_POSTRequestLoader) {
     _POSTRequestLoader.reset([[CRWJSPOSTRequestLoader alloc] init]);
   }
@@ -4056,17 +4058,16 @@ const NSTimeInterval kSnapshotOverlayTransition = 0.5;
   CRWWKScriptMessageRouter* messageRouter =
       [self webViewConfigurationProvider].GetScriptMessageRouter();
 
-  [_POSTRequestLoader loadPOSTRequest:request
-                            inWebView:_webView
-                        messageRouter:messageRouter
-                    completionHandler:^(NSError* loadError) {
-                      if (loadError)
-                        [self handleLoadError:loadError
-                                  inMainFrame:YES
-                                forNavigation:nil];
-                      else
-                        self.webStateImpl->SetContentsMimeType("text/html");
-                    }];
+  return [_POSTRequestLoader
+        loadPOSTRequest:request
+              inWebView:_webView
+          messageRouter:messageRouter
+      completionHandler:^(NSError* loadError) {
+        if (loadError)
+          [self handleLoadError:loadError inMainFrame:YES forNavigation:nil];
+        else
+          self.webStateImpl->SetContentsMimeType("text/html");
+      }];
 }
 
 - (void)loadHTML:(NSString*)HTML forURL:(const GURL&)URL {