jni_generator: Pass object parameters as JavaParamRef.

components/cronet/android/cronet_histogram_manager.cc

 // Copyright 2014 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 "components/cronet/android/cronet_histogram_manager.h"
 
 #include <string>
 #include <vector>
 
 #include "base/android/jni_array.h"
 #include "base/metrics/statistics_recorder.h"
 #include "components/cronet/histogram_manager.h"
 
 #include "jni/CronetHistogramManager_jni.h"
 
 namespace cronet {
 
 // Explicitly register static JNI functions.
 bool CronetHistogramManagerRegisterJni(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
-static void EnsureInitialized(JNIEnv* env, jobject jcaller) {
+static void EnsureInitialized(JNIEnv* env,
+                              const JavaParamRef<jobject>& jcaller) {
   base::StatisticsRecorder::Initialize();
 }
 
-static ScopedJavaLocalRef<jbyteArray> GetHistogramDeltas(JNIEnv* env,
-                                                         jobject jcaller) {
+static ScopedJavaLocalRef<jbyteArray> GetHistogramDeltas(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& jcaller) {
   std::vector<uint8> data;
   if (!HistogramManager::GetInstance()->GetDeltas(&data))
     return ScopedJavaLocalRef<jbyteArray>();
   return base::android::ToJavaByteArray(env, &data[0], data.size());
 }
 
 }  // namespace cronet