Reland of Rename RTPVideoHeader.isFirstPacket to .is_first_packet_in_frame.

webrtc/modules/video_coding/video_coding_robustness_unittest.cc

Index: webrtc/modules/video_coding/video_coding_robustness_unittest.cc
diff --git a/webrtc/modules/video_coding/video_coding_robustness_unittest.cc b/webrtc/modules/video_coding/video_coding_robustness_unittest.cc
index f407ba209400809b473735b4029262669ba3699d..55a05720c31137f76b07206fa6f60d2f2908cdd5 100644
--- a/webrtc/modules/video_coding/video_coding_robustness_unittest.cc
+++ b/webrtc/modules/video_coding/video_coding_robustness_unittest.cc
@@ -66,7 +66,7 @@ class VCMRobustnessTest : public ::testing::Test {
     rtp_info.header.payloadType = video_codec_.plType;
     rtp_info.type.Video.codec = kRtpVideoVp8;
     rtp_info.type.Video.codecHeader.VP8.InitRTPVideoHeaderVP8();
-    rtp_info.type.Video.isFirstPacket = first;
+    rtp_info.type.Video.is_first_packet_in_frame = first;
 
     ASSERT_EQ(VCM_OK, vcm_->IncomingPacket(payload, kPayloadLen, rtp_info));
   }