Add Cast PLI support on sender side.

media/cast/net/rtcp/rtcp_utility_unittest.cc

Index: media/cast/net/rtcp/rtcp_utility_unittest.cc
diff --git a/media/cast/net/rtcp/rtcp_utility_unittest.cc b/media/cast/net/rtcp/rtcp_utility_unittest.cc
index 4eed746297e42b9e5fba1612b6fcacb64d87d2ab..0077c8102a099e2bb845918e23b6182fce76ba05 100644
--- a/media/cast/net/rtcp/rtcp_utility_unittest.cc
+++ b/media/cast/net/rtcp/rtcp_utility_unittest.cc
@@ -341,6 +341,28 @@ TEST_F(RtcpParserTest, ExtendedCastFeedbackDoesNotBreakParsing) {
   ExpectCastFeedback(parser);
 }
 
+TEST_F(RtcpParserTest, InjectReceiverReportPli) {
+  // Expect to be ignored since the sender ssrc does not match.
+  TestRtcpPacketBuilder builder1;
+  builder1.AddPli(kUnknownSsrc, kSourceSsrc);
+  RtcpParser parser1(kSourceSsrc, kSenderSsrc);

[Irfan, 2016/02/29 16:01:23]

I find kSourceSssrc and kSenderSsrc unclear. Should they be renamed kLocalSsrc
kRemoteSsrc ?

[xjz, 2016/02/29 19:48:58]

Done.

+  EXPECT_TRUE(parser1.Parse(builder1.Reader()));
+  EXPECT_FALSE(parser1.has_picture_loss_indicator());
+
+  // Expect to be ignored since the receiver ssrc does not match.
+  TestRtcpPacketBuilder builder2;
+  builder2.AddPli(kSenderSsrc, kUnknownSsrc);
+  RtcpParser parser2(kSourceSsrc, kSenderSsrc);
+  EXPECT_TRUE(parser2.Parse(builder2.Reader()));
+  EXPECT_FALSE(parser2.has_picture_loss_indicator());
+
+  TestRtcpPacketBuilder builder3;
+  builder3.AddPli(kSenderSsrc, kSourceSsrc);
+  RtcpParser parser3(kSourceSsrc, kSenderSsrc);
+  EXPECT_TRUE(parser3.Parse(builder3.Reader()));
+  EXPECT_TRUE(parser3.has_picture_loss_indicator());
+}
+
 TEST_F(RtcpParserTest, InjectReceiverReportWithReceiverLogVerificationBase) {
   static const uint32_t kTimeBaseMs = 12345678;
   static const uint32_t kTimeDelayMs = 10;