jni_generator: Pass object parameters as JavaParamRef.

base/android/animation_frame_time_histogram.cc

Index: base/android/animation_frame_time_histogram.cc
diff --git a/base/android/animation_frame_time_histogram.cc b/base/android/animation_frame_time_histogram.cc
index 0d796193829ccebde22d7eadf7b30015ea27509f..2cf7516ff2bdfd8e8e144087686cb533b46d5adf 100644
--- a/base/android/animation_frame_time_histogram.cc
+++ b/base/android/animation_frame_time_histogram.cc
@@ -10,9 +10,9 @@
 
 // static
 void SaveHistogram(JNIEnv* env,
-                   jobject jcaller,
-                   jstring j_histogram_name,
-                   jlongArray j_frame_times_ms,
+                   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(