Correct iOS build for latest Xcode beta.

ios/web/test/crw_fake_web_controller_observer.mm

Index: ios/web/test/crw_fake_web_controller_observer.mm
diff --git a/ios/web/test/crw_fake_web_controller_observer.mm b/ios/web/test/crw_fake_web_controller_observer.mm
index 18081684eb8cb6b587dc4349311a498a991a773e..c15553fc71dcb9a37398a67e2875e11e50a06a12 100644
--- a/ios/web/test/crw_fake_web_controller_observer.mm
+++ b/ios/web/test/crw_fake_web_controller_observer.mm
@@ -15,11 +15,6 @@
 
 @synthesize pageLoaded = _pageLoaded;
 
-- (instancetype)init {
-  NOTREACHED();
-  return nil;
-}
-
 - (instancetype)initWithCommandPrefix:(NSString*)commandPrefix {
   DCHECK(commandPrefix);
   self = [super init];
@@ -29,6 +24,11 @@
   return self;
 }
 
+- (instancetype)init {
+  NOTREACHED();
+  return nil;
+}
+
 - (void)pageLoaded:(CRWWebController*)webController {
   _pageLoaded = YES;
 }