MSE - Fix crash caused by incorrect GC of GOP with next buffer position

media/filters/source_buffer_range.cc

Index: media/filters/source_buffer_range.cc
diff --git a/media/filters/source_buffer_range.cc b/media/filters/source_buffer_range.cc
index bd99bc01d3c395d099b061d94fda12607ba05818..cd9e8d89d904260d05a6d14d4e2443180dfd8992 100644
--- a/media/filters/source_buffer_range.cc
+++ b/media/filters/source_buffer_range.cc
@@ -231,7 +231,9 @@ bool SourceBufferRange::TruncateAt(
 }
 
 size_t SourceBufferRange::DeleteGOPFromFront(BufferQueue* deleted_buffers) {
-  DCHECK(!FirstGOPContainsNextBufferPosition());
+  CHECK(!buffers_.empty());
+  CHECK(!FirstGOPContainsNextBufferPosition());
+
   DCHECK(deleted_buffers);
 
   int buffers_deleted = 0;
@@ -279,7 +281,9 @@ size_t SourceBufferRange::DeleteGOPFromFront(BufferQueue* deleted_buffers) {
 }
 
 size_t SourceBufferRange::DeleteGOPFromBack(BufferQueue* deleted_buffers) {
-  DCHECK(!LastGOPContainsNextBufferPosition());
+  CHECK(!buffers_.empty());
+  CHECK(!LastGOPContainsNextBufferPosition());
+
   DCHECK(deleted_buffers);
 
   // Remove the last GOP's keyframe from the |keyframe_map_|.
@@ -476,7 +480,7 @@ void SourceBufferRange::ResetNextBufferPosition() {
 void SourceBufferRange::AppendRangeToEnd(const SourceBufferRange& range,
                                          bool transfer_current_position) {
   DCHECK(CanAppendRangeToEnd(range));
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
 
   if (transfer_current_position && range.next_buffer_index_ >= 0)
     next_buffer_index_ = range.next_buffer_index_ + buffers_.size();
@@ -491,13 +495,13 @@ bool SourceBufferRange::CanAppendRangeToEnd(
 
 bool SourceBufferRange::CanAppendBuffersToEnd(
     const BufferQueue& buffers) const {
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
   return IsNextInSequence(buffers.front()->GetDecodeTimestamp(),
                           buffers.front()->is_key_frame());
 }
 
 bool SourceBufferRange::BelongsToRange(DecodeTimestamp timestamp) const {
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
 
   return (IsNextInSequence(timestamp, false) ||
           (GetStartTimestamp() <= timestamp && timestamp <= GetEndTimestamp()));
@@ -522,7 +526,7 @@ bool SourceBufferRange::EndOverlaps(const SourceBufferRange& range) const {
 }
 
 DecodeTimestamp SourceBufferRange::GetStartTimestamp() const {
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
   DecodeTimestamp start_timestamp = media_segment_start_time_;
   if (start_timestamp == kNoDecodeTimestamp())
     start_timestamp = buffers_.front()->GetDecodeTimestamp();
@@ -530,12 +534,12 @@ DecodeTimestamp SourceBufferRange::GetStartTimestamp() const {
 }
 
 DecodeTimestamp SourceBufferRange::GetEndTimestamp() const {
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
   return buffers_.back()->GetDecodeTimestamp();
 }
 
 DecodeTimestamp SourceBufferRange::GetBufferedEndTimestamp() const {
-  DCHECK(!buffers_.empty());
+  CHECK(!buffers_.empty());
   base::TimeDelta duration = buffers_.back()->duration();
   if (duration == kNoTimestamp() || duration == base::TimeDelta())
     duration = GetApproximateDuration();