jni: Pass method parameters as JavaParamRef in content.

content/browser/time_zone_monitor_android.h

Index: content/browser/time_zone_monitor_android.h
diff --git a/content/browser/time_zone_monitor_android.h b/content/browser/time_zone_monitor_android.h
index cb3cb9f216e1be71c767c06df6c13afff4877b85..77141119626d2e9dd630378f35d2029d4eac3c65 100644
--- a/content/browser/time_zone_monitor_android.h
+++ b/content/browser/time_zone_monitor_android.h
@@ -23,7 +23,9 @@ class TimeZoneMonitorAndroid : public TimeZoneMonitor {
   static bool Register(JNIEnv* env);
 
   // Called by the Java implementation when the system time zone changes.
-  void TimeZoneChangedFromJava(JNIEnv* env, jobject caller);
+  void TimeZoneChangedFromJava(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& caller);
 
  private:
   // Java provider of system time zone change notifications.