Revert "Add metrics for certificate report uploads"

chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h

Index: chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h
diff --git a/chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h b/chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h
index 7c4d979fd9405c8a0f6f5f3a0d06421ee94d325f..4ac99fa95fa06f513f5293006ee8b6e512ef54a5 100644
--- a/chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h
+++ b/chrome/browser/safe_browsing/certificate_reporting_service_test_utils.h
@@ -9,7 +9,6 @@
 
 #include "base/macros.h"
 #include "base/run_loop.h"
-#include "base/test/histogram_tester.h"
 #include "base/threading/non_thread_safe.h"
 #include "chrome/browser/safe_browsing/certificate_reporting_service.h"
 #include "content/public/test/test_browser_thread.h"
@@ -241,28 +240,6 @@ class CertificateReportingServiceTestHelper {
   DISALLOW_COPY_AND_ASSIGN(CertificateReportingServiceTestHelper);
 };
 
-// Class to test reporting events histogram for CertificateReportingService.
-// We can't use a simple HistogramTester, as we need to wait until test teardown
-// to check the histogram contents. This ensures that all in-flight requests
-// are torn down by the time we check the histograms.
-class EventHistogramTester {
- public:
-  EventHistogramTester();
-  ~EventHistogramTester();
-
-  void SetExpectedValues(int submitted,
-                         int failed,
-                         int successful,
-                         int dropped);
-
- private:
-  int submitted_ = 0;
-  int failed_ = 0;
-  int successful_ = 0;
-  int dropped_ = 0;
-  base::HistogramTester histogram_tester_;
-};
-
 }  // namespace certificate_reporting_test_utils
 
 #endif  // CHROME_BROWSER_SAFE_BROWSING_CERTIFICATE_REPORTING_SERVICE_TEST_UTILS_H_