Remove URLRequestJob::GetResponseCode implementations from some tests.

components/domain_reliability/uploader_unittest.cc

Index: components/domain_reliability/uploader_unittest.cc
diff --git a/components/domain_reliability/uploader_unittest.cc b/components/domain_reliability/uploader_unittest.cc
index 0b99fc0655df8652868801a508cd2c30c8515e5b..35b88be3f08dbc53ff24e9d2f090a428c24134b9 100644
--- a/components/domain_reliability/uploader_unittest.cc
+++ b/components/domain_reliability/uploader_unittest.cc
@@ -95,10 +95,6 @@ class UploadMockURLRequestJob : public net::URLRequestJob {
       NotifyStartError(net::URLRequestStatus::FromError(result_.net_error));
   }
 
-  int GetResponseCode() const override {
-    return result_.response_code;
-  }
-
   void GetResponseInfo(net::HttpResponseInfo* info) override {
     info->headers = result_.response_headers;
   }