校验host是否有值

GMRouter/Classes/GMRouter+gm.m

@@ -191,7 +191,7 @@ static NSMutableDictionary *routeMap = nil;
         //拦截所有的即将调转的url(value),如果不在白名单之中,让其使用GMThirdWebViewController加载.
        NSString *valueHost = [[NSURL URLWithString:value] host];
        Class cls = NSClassFromString(@"GMServerDomains");
-       if ([cls respondsToSelector:@selector(allowURLHost:)]) {
+        if (valueHost.length != 0 && [cls respondsToSelector:@selector(allowURLHost:)]) {
          BOOL isAllow = [cls performSelector:@selector(allowURLHost:) withObject:valueHost];
            if (!isAllow) {
                 host = @"third_webview";