Allowing a Java object field to be null in a new JNI helper method.

webrtc/api/java/jni/peerconnection_jni.cc

Index: webrtc/api/java/jni/peerconnection_jni.cc
diff --git a/webrtc/api/java/jni/peerconnection_jni.cc b/webrtc/api/java/jni/peerconnection_jni.cc
index cf3ddebde96c49b22b736a38b38e949a9175d6c2..e79337d0aa232184613b98b022292fedb2cefd7a 100644
--- a/webrtc/api/java/jni/peerconnection_jni.cc
+++ b/webrtc/api/java/jni/peerconnection_jni.cc
@@ -2042,7 +2042,8 @@ static bool JavaEncodingToJsepRtpEncodingParameters(
   for (jobject j_encoding_parameters : Iterable(jni, j_encodings)) {
     webrtc::RtpEncodingParameters encoding;
     encoding.active = GetBooleanField(jni, j_encoding_parameters, active_id);
-    jobject j_bitrate = GetObjectField(jni, j_encoding_parameters, bitrate_id);
+    jobject j_bitrate =
+        GetNullableObjectField(jni, j_encoding_parameters, bitrate_id);
     if (!IsNull(jni, j_bitrate)) {
       int bitrate_value = jni->CallIntMethod(j_bitrate, int_value_id);
       CHECK_EXCEPTION(jni) << "error during CallIntMethod";