Allow trailing whitespace in RTSP SessionDescription lines

This CL fixes the parser for the RTSP SessionDescription such that it will not choke if there is trailing whitespace in the lines.

PiperOrigin-RevId: 750158624

RELEASENOTES.md

@@ -73,6 +73,9 @@
 *   DASH extension:
 *   Smooth Streaming extension:
 *   RTSP extension:
+    *   Add parsing support for SessionDescriptions containing lines with
+        trailing whitespace characters
+        ([#2357](https://github.com/androidx/media/issues/2357)).
 *   Decoder extensions (FFmpeg, VP9, AV1, etc.):
 *   MIDI extension:
 *   Leanback extension:

libraries/exoplayer_rtsp/src/main/java/androidx/media3/exoplayer/rtsp/SessionDescriptionParser.java

@@ -83,6 +83,8 @@ import java.util.regex.Pattern;
 
     // Lines are separated by an CRLF.
     for (String line : RtspMessageUtil.splitRtspMessageBody(sdpString)) {
+      line = line.trim();
+
       if ("".equals(line)) {
         continue;
       }

libraries/exoplayer_rtsp/src/test/java/androidx/media3/exoplayer/rtsp/SessionDescriptionTest.java

@@ -342,6 +342,25 @@ public class SessionDescriptionTest {
     assertThat(sessionDescription.mediaDescriptionList.get(0).mediaTitle).isNull();
   }
 
+  @Test
+  public void parse_sdpStringWithTrailingWhitespace_succeeds() throws Exception {
+    String testMediaSdpInfo =
+        "v=0\r\n"
+            + "o=MNobody 2890844526 2890842807 IN IP4 192.0.2.46\r\n"
+            + "s=SDP Seminar\r\n"
+            + "i=Sun Apr 20 12:59:09 2025\n\r\n"
+            + "t=0 0\r\n"
+            + "a=control:*\r\n"
+            + "m=audio 3456 RTP/AVP 0\r\n"
+            + "i=\r\n"
+            + "a=rtpmap:97 AC3/44100  \r\n";
+
+    SessionDescription sessionDescription = SessionDescriptionParser.parse(testMediaSdpInfo);
+
+    assertThat(sessionDescription.sessionInfo).isEqualTo("Sun Apr 20 12:59:09 2025");
+    assertThat(sessionDescription.mediaDescriptionList.get(0).mediaTitle).isNull();
+  }
+
   @Test
   public void parse_sdpStringWithEmptySessionAttribute_throwsParserException() {
     String testMediaSdpInfo =