Refactor composing report blocks for rtcp Sender/Receiver reports

webrtc/modules/rtp_rtcp/source/rtcp_packet/sender_report_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 93 matching lines @@
   const size_t kMaxReportBlocks = (1 << 5) - 1;
   ReportBlock rb;
   for (size_t i = 0; i < kMaxReportBlocks; ++i) {
     rb.SetMediaSsrc(kRemoteSsrc + i);
     EXPECT_TRUE(sr.AddReportBlock(rb));
   }
   rb.SetMediaSsrc(kRemoteSsrc + kMaxReportBlocks);
   EXPECT_FALSE(sr.AddReportBlock(rb));
 }
 
+TEST(RtcpPacketSenderReportTest, SetReportBlocksOverwritesOldBlocks) {
+  SenderReport sr;
+  sr.AddReportBlock(ReportBlock());
+  ASSERT_EQ(sr.report_blocks().size(), 1u);
+
+  std::vector<ReportBlock> blocks(3);
+  EXPECT_TRUE(sr.SetReportBlocks(blocks));
+  EXPECT_EQ(sr.report_blocks().size(), 3u);
+}
+
+TEST(RtcpPacketSenderReportTest, SetTooManyReportBlocks) {
+  SenderReport sr;
+  const size_t kMaxReportBlocks = (1 << 5) - 1;
+
+  std::vector<ReportBlock> blocks(kMaxReportBlocks);
+  EXPECT_TRUE(sr.SetReportBlocks(blocks));
+
+  blocks.push_back(ReportBlock());
+  EXPECT_FALSE(sr.SetReportBlocks(blocks));
+}
+
 }  // namespace webrtc