[MSE] Fix GC with media_time past the last appended buffer timestamp

media/filters/source_buffer_stream_unittest.cc

Index: media/filters/source_buffer_stream_unittest.cc
diff --git a/media/filters/source_buffer_stream_unittest.cc b/media/filters/source_buffer_stream_unittest.cc
index 5d8dfd5d29b334018653a588c7513c0bfaab30fe..45cec1332388dfefeeeea5bc7aca95f750d762a2 100644
--- a/media/filters/source_buffer_stream_unittest.cc
+++ b/media/filters/source_buffer_stream_unittest.cc
@@ -3061,6 +3061,26 @@ TEST_F(SourceBufferStreamTest, GarbageCollection_Performance) {
   }
 }
 
+TEST_F(SourceBufferStreamTest, GarbageCollection_MediaTimeAfterLastAppend) {
+  // Set memory limit to 10 buffers.
+  SetMemoryLimit(10);
+
+  // Append 12 buffers. The duration of the last buffer is 30
+  NewSegmentAppend("0K 30 60 90 120K 150 180 210K 240 270 300K 330D30");
+  CheckExpectedRangesByTimestamp("{ [0,360) }");
+
+  // Do a garbage collection with the media time higher than the timestamp of
+  // the last appended buffer (330), but still within buffered ranges, taking
+  // into account the duration of the last frame (timestamp of the last frame is
+  // 330, duration is 30, so the latest valid buffered position is 330+30=360).
+  EXPECT_TRUE(stream_->GarbageCollectIfNeeded(
+      DecodeTimestamp::FromMilliseconds(360), 0));
+
+  // GC should collect one GOP from the front to bring us back under memory
+  // limit of 10 buffers.
+  CheckExpectedRangesByTimestamp("{ [120,360) }");
+}
+
 TEST_F(SourceBufferStreamTest, GetRemovalRange_BytesToFree) {
   // Append 2 GOPs starting at 300ms, 30ms apart.
   NewSegmentAppend("300K 330 360 390K 420 450");