Add missing using statements for JNI types.

chrome/browser/android/metrics/uma_utils.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/android/metrics/uma_utils.h"
 
 #include <stdint.h>
 
 #include "chrome/browser/browser_process.h"
 #include "components/metrics/metrics_reporting_default_state.h"
 #include "jni/UmaUtils_jni.h"
 
+using base::android::JavaParamRef;
+
 class PrefService;
 
 namespace chrome {
 namespace android {
 
 base::Time GetMainEntryPointTime() {
   JNIEnv* env = base::android::AttachCurrentThread();
   int64_t startTimeUnixMs = Java_UmaUtils_getMainEntryPointWallTime(env);
   return base::Time::UnixEpoch() +
          base::TimeDelta::FromMilliseconds(startTimeUnixMs);
 }
 
 static void RecordMetricsReportingDefaultOptIn(JNIEnv* env,
                                                const JavaParamRef<jclass>& obj,
                                                jboolean opt_in) {
   DCHECK(g_browser_process);
   PrefService* local_state = g_browser_process->local_state();
   metrics::RecordMetricsReportingDefaultState(
       local_state, opt_in ? metrics::EnableMetricsDefault::OPT_IN
                           : metrics::EnableMetricsDefault::OPT_OUT);
 }
 
 bool RegisterStartupMetricUtils(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace chrome