Add test for emsg near to end of DASH period

The dumped output should include metadata, but doesn't because of
Issue: #8710. The fix is in a follow-up change.
PiperOrigin-RevId: 366028303

library/dash/src/test/java/com/google/android/exoplayer2/e2etest/DashPlaybackTest.java

@@ -73,4 +73,27 @@ public void webvttInMp4() throws Exception {
     DumpFileAsserts.assertOutput(
         applicationContext, playbackOutput, "playbackdumps/dash/webvtt-in-mp4.dump");
   }
+
+  // https://github.com/google/ExoPlayer/issues/8710
+  @Test
+  public void emsgNearToPeriodBoundary() throws Exception {
+    Context applicationContext = ApplicationProvider.getApplicationContext();
+    CapturingRenderersFactory capturingRenderersFactory =
+        new CapturingRenderersFactory(applicationContext);
+    SimpleExoPlayer player =
+        new SimpleExoPlayer.Builder(applicationContext, capturingRenderersFactory)
+            .setClock(new FakeClock(/* isAutoAdvancing= */ true))
+            .build();
+    player.setVideoSurface(new Surface(new SurfaceTexture(/* texName= */ 1)));
+    PlaybackOutput playbackOutput = PlaybackOutput.register(player, capturingRenderersFactory);
+
+    player.setMediaItem(MediaItem.fromUri("asset:///media/dash/emsg/sample.mpd"));
+    player.prepare();
+    player.play();
+    TestPlayerRunHelper.runUntilPlaybackState(player, Player.STATE_ENDED);
+    player.release();
+
+    DumpFileAsserts.assertOutput(
+        applicationContext, playbackOutput, "playbackdumps/dash/emsg.dump");
+  }
 }

testdata/src/test/assets/media/dash/emsg/sample.mpd

@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--Generated with https://github.com/google/shaka-packager version v2.4.1-c731217-release
+$ packager-linux \
+   in=../../mp4/sample.mp4,stream=audio,output=sample.audio.mp4 \
+   -\-mpd_output sample.mpd
+
+   Then EventStream section & second period added by hand (copy-pasting first period).
+-->
+<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" minBufferTime="PT2S" type="static" mediaPresentationDuration="PT2.044S">
+  <Period id="0" start="PT00.000S">
+    <AdaptationSet id="0" contentType="audio" subsegmentAlignment="true">
+      <Representation id="0" bandwidth="78099" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="1"/>
+        <BaseURL>sample.audio.mp4</BaseURL>
+        <SegmentBase indexRange="757-800" timescale="44100" presentationTimeOffset="1940">
+          <Initialization range="0-756"/>
+        </SegmentBase>
+      </Representation>
+    </AdaptationSet>
+    <EventStream schemeIdUri="urn:mpeg:dash:event:callback:2015" timescale="1000" value="1">
+      <Event presentationTime="100" duration="1000" id="0" messageData="" />
+      <Event presentationTime="1000" duration="1000" id="1" messageData="" />
+    </EventStream>
+  </Period>
+  <Period id="1" start="PT1.022S">
+    <AdaptationSet id="0" contentType="audio" subsegmentAlignment="true">
+      <Representation id="0" bandwidth="78099" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="1"/>
+        <BaseURL>sample.audio.mp4</BaseURL>
+        <SegmentBase indexRange="757-800" timescale="44100" presentationTimeOffset="1940">
+          <Initialization range="0-756"/>
+        </SegmentBase>
+      </Representation>
+    </AdaptationSet>
+  </Period>
+</MPD>

testdata/src/test/assets/playbackdumps/dash/emsg.dump

@@ -0,0 +1,94 @@
+MediaCodecAdapter (exotest.audio.aac):
+  buffers.length = 92
+  buffers[0] = length 23, hash 47DE9131
+  buffers[1] = length 6, hash 31EC5206
+  buffers[2] = length 148, hash 894A176B
+  buffers[3] = length 189, hash CEF235A1
+  buffers[4] = length 205, hash BBF5F7B0
+  buffers[5] = length 210, hash F278B193
+  buffers[6] = length 210, hash 82DA1589
+  buffers[7] = length 207, hash 5BE231DF
+  buffers[8] = length 225, hash 18819EE1
+  buffers[9] = length 215, hash CA7FA67B
+  buffers[10] = length 211, hash 581A1C18
+  buffers[11] = length 216, hash ADB88187
+  buffers[12] = length 229, hash 2E8BA4DC
+  buffers[13] = length 232, hash 22F0C510
+  buffers[14] = length 235, hash 867AD0DC
+  buffers[15] = length 231, hash 84E823A8
+  buffers[16] = length 226, hash 1BEF3A95
+  buffers[17] = length 216, hash EAA345AE
+  buffers[18] = length 229, hash 6957411F
+  buffers[19] = length 219, hash 41275022
+  buffers[20] = length 241, hash 6495DF96
+  buffers[21] = length 228, hash 63D95906
+  buffers[22] = length 238, hash 34F676F9
+  buffers[23] = length 234, hash E5CBC045
+  buffers[24] = length 231, hash 5FC43661
+  buffers[25] = length 217, hash 682708ED
+  buffers[26] = length 239, hash D43780FC
+  buffers[27] = length 243, hash C5E17980
+  buffers[28] = length 231, hash AC5837BA
+  buffers[29] = length 230, hash 169EE895
+  buffers[30] = length 238, hash C48FF3F1
+  buffers[31] = length 225, hash 531E4599
+  buffers[32] = length 232, hash CB3C6B8D
+  buffers[33] = length 243, hash F8C94C7
+  buffers[34] = length 232, hash A646A7D0
+  buffers[35] = length 237, hash E8B787A5
+  buffers[36] = length 228, hash 3FA7A29F
+  buffers[37] = length 235, hash B9B33B0A
+  buffers[38] = length 264, hash 71A4869E
+  buffers[39] = length 257, hash D049B54C
+  buffers[40] = length 227, hash 66757231
+  buffers[41] = length 227, hash BD374F1B
+  buffers[42] = length 235, hash 999477F6
+  buffers[43] = length 229, hash FFF98DF0
+  buffers[44] = length 6, hash 31B22286
+  buffers[45] = length 0, hash 1
+  buffers[46] = length 23, hash 47DE9131
+  buffers[47] = length 6, hash 31EC5206
+  buffers[48] = length 148, hash 894A176B
+  buffers[49] = length 189, hash CEF235A1
+  buffers[50] = length 205, hash BBF5F7B0
+  buffers[51] = length 210, hash F278B193
+  buffers[52] = length 210, hash 82DA1589
+  buffers[53] = length 207, hash 5BE231DF
+  buffers[54] = length 225, hash 18819EE1
+  buffers[55] = length 215, hash CA7FA67B
+  buffers[56] = length 211, hash 581A1C18
+  buffers[57] = length 216, hash ADB88187
+  buffers[58] = length 229, hash 2E8BA4DC
+  buffers[59] = length 232, hash 22F0C510
+  buffers[60] = length 235, hash 867AD0DC
+  buffers[61] = length 231, hash 84E823A8
+  buffers[62] = length 226, hash 1BEF3A95
+  buffers[63] = length 216, hash EAA345AE
+  buffers[64] = length 229, hash 6957411F
+  buffers[65] = length 219, hash 41275022
+  buffers[66] = length 241, hash 6495DF96
+  buffers[67] = length 228, hash 63D95906
+  buffers[68] = length 238, hash 34F676F9
+  buffers[69] = length 234, hash E5CBC045
+  buffers[70] = length 231, hash 5FC43661
+  buffers[71] = length 217, hash 682708ED
+  buffers[72] = length 239, hash D43780FC
+  buffers[73] = length 243, hash C5E17980
+  buffers[74] = length 231, hash AC5837BA
+  buffers[75] = length 230, hash 169EE895
+  buffers[76] = length 238, hash C48FF3F1
+  buffers[77] = length 225, hash 531E4599
+  buffers[78] = length 232, hash CB3C6B8D
+  buffers[79] = length 243, hash F8C94C7
+  buffers[80] = length 232, hash A646A7D0
+  buffers[81] = length 237, hash E8B787A5
+  buffers[82] = length 228, hash 3FA7A29F
+  buffers[83] = length 235, hash B9B33B0A
+  buffers[84] = length 264, hash 71A4869E
+  buffers[85] = length 257, hash D049B54C
+  buffers[86] = length 227, hash 66757231
+  buffers[87] = length 227, hash BD374F1B
+  buffers[88] = length 235, hash 999477F6
+  buffers[89] = length 229, hash FFF98DF0
+  buffers[90] = length 6, hash 31B22286
+  buffers[91] = length 0, hash 1