Correct iOS build for latest Xcode beta.

ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm

Index: ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm
diff --git a/ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm b/ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm
index c6f015e5bdf880711cc39fe9e98cfd0b90d775dd..2dd10ab69cdab64bb3ea16f2547c5285cdd43688 100644
--- a/ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm
+++ b/ios/web/web_state/ui/crw_wk_web_view_crash_detector.mm
@@ -45,11 +45,6 @@ BOOL IsWebViewTerminationError(NSError* error) {
   base::mac::ScopedBlock<ProceduralBlock> _crashHandler;
 }
 
-- (instancetype)init {
-  NOTREACHED();
-  return nil;
-}
-
 - (instancetype)initWithWebView:(WKWebView*)webView
                    crashHandler:(ProceduralBlock)handler {
   DCHECK(webView);
@@ -71,6 +66,11 @@ BOOL IsWebViewTerminationError(NSError* error) {
   return self;
 }
 
+- (instancetype)init {
+  NOTREACHED();
+  return nil;
+}
+
 - (void)dealloc {
   [_webView removeObserver:self forKeyPath:kCrashIndicatorKeyPath];
   [super dealloc];