Expose audio_jitter_buffer_fast_accelerate config to objc wrapper

NOTRY=True
BUG=webrtc:6827

Review-Url: https://codereview.webrtc.org/2556553002
Cr-Commit-Position: refs/heads/master@{#15429}
diff --git a/webrtc/sdk/objc/Framework/UnitTests/RTCConfigurationTest.mm b/webrtc/sdk/objc/Framework/UnitTests/RTCConfigurationTest.mm
index 1fca960..79ffd17 100644
--- a/webrtc/sdk/objc/Framework/UnitTests/RTCConfigurationTest.mm
+++ b/webrtc/sdk/objc/Framework/UnitTests/RTCConfigurationTest.mm
@@ -40,6 +40,7 @@
   const int timeout = 1;
   const int interval = 2;
   config.audioJitterBufferMaxPackets = maxPackets;
+  config.audioJitterBufferFastAccelerate = YES;
   config.iceConnectionReceivingTimeout = timeout;
   config.iceBackupCandidatePairPingInterval = interval;
   config.continualGatheringPolicy =
@@ -65,6 +66,7 @@
   EXPECT_EQ(webrtc::PeerConnectionInterface::kCandidateNetworkPolicyLowCost,
             nativeConfig->candidate_network_policy);
   EXPECT_EQ(maxPackets, nativeConfig->audio_jitter_buffer_max_packets);
+  EXPECT_EQ(true, nativeConfig->audio_jitter_buffer_fast_accelerate);
   EXPECT_EQ(timeout, nativeConfig->ice_connection_receiving_timeout);
   EXPECT_EQ(interval, nativeConfig->ice_backup_candidate_pair_ping_interval);
   EXPECT_EQ(webrtc::PeerConnectionInterface::GATHER_CONTINUALLY,