Don't detect a new frame if a previous packet is used in a previous frame.

webrtc/modules/video_coding/video_packet_buffer_unittest.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 450 matching lines @@
   EXPECT_TRUE(Insert(2, kKeyFrame, kFirst, kNotLast, 5, data2));
 
   // Expect to free data3 upon insertion (old packet).
   packet_buffer_->ClearTo(1);
   EXPECT_FALSE(Insert(1, kKeyFrame, kFirst, kNotLast, 5, data3));
 
   // Expect to free data4 upon insertion (packet buffer is full).
   EXPECT_FALSE(Insert(2 + kMaxSize, kKeyFrame, kFirst, kNotLast, 5, data4));
 }
 
+TEST_F(TestPacketBuffer, ContinuousSeqNumDoubleMarkerBit) {
+  Insert(2, kKeyFrame, kNotFirst, kNotLast);
+  Insert(1, kKeyFrame, kFirst, kLast);
+  frames_from_callback_.clear();
+  Insert(3, kKeyFrame, kNotFirst, kLast);
+
+  EXPECT_EQ(0UL, frames_from_callback_.size());
+}
+
 }  // namespace video_coding
 }  // namespace webrtc