Add missing using statements for JNI types.

base/android/animation_frame_time_histogram.cc

 // Copyright 2015 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 "base/android/animation_frame_time_histogram.h"
 
 #include "base/android/jni_string.h"
 #include "base/metrics/histogram_macros.h"
 #include "jni/AnimationFrameTimeHistogram_jni.h"
 
+using base::android::JavaParamRef;
+
 // static
 void SaveHistogram(JNIEnv* env,
                    const JavaParamRef<jobject>& jcaller,
                    const JavaParamRef<jstring>& j_histogram_name,
                    const JavaParamRef<jlongArray>& j_frame_times_ms,
                    jint j_count) {
   jlong *frame_times_ms = env->GetLongArrayElements(j_frame_times_ms, NULL);
   std::string histogram_name = base::android::ConvertJavaStringToUTF8(
       env, j_histogram_name);
 
   for (int i = 0; i < j_count; ++i) {
     UMA_HISTOGRAM_TIMES(histogram_name.c_str(),
                         base::TimeDelta::FromMilliseconds(frame_times_ms[i]));
   }
 }
 
 namespace base {
 namespace android {
 
 // static
 bool RegisterAnimationFrameTimeHistogram(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace base