Encrypted Media: Support config change in DecryptingDemuxerStream.

media/filters/source_buffer_stream.cc

Index: media/filters/source_buffer_stream.cc
diff --git a/media/filters/source_buffer_stream.cc b/media/filters/source_buffer_stream.cc
index 5507acc7c4b5134ef2c5b636432e2a4ed7a5364b..3f1b42d82662bc262607896ee3c1daa15e58e157 100644
--- a/media/filters/source_buffer_stream.cc
+++ b/media/filters/source_buffer_stream.cc
@@ -557,7 +557,6 @@ int SourceBufferStream::FreeBuffers(int total_bytes_to_free,
   SourceBufferRange* new_range_for_append = NULL;
 
   while (!ranges_.empty() && bytes_to_free > 0) {
-
     SourceBufferRange* current_range = NULL;
     BufferQueue buffers;
     int bytes_deleted = 0;
@@ -1061,6 +1060,11 @@ bool SourceBufferStream::UpdateAudioConfig(const AudioDecoderConfig& config) {
     return false;
   }
 
+  if (audio_configs_[0]->is_encrypted() != config.is_encrypted()) {
+    MEDIA_LOG(log_cb_) << "Audio encryption changes not allowed.";
+    return false;
+  }
+
   // Check to see if the new config matches an existing one.
   for (size_t i = 0; i < audio_configs_.size(); ++i) {
     if (config.Matches(*audio_configs_[i])) {
@@ -1091,6 +1095,11 @@ bool SourceBufferStream::UpdateVideoConfig(const VideoDecoderConfig& config) {
     return false;
   }
 
+  if (video_configs_[0]->is_encrypted() != config.is_encrypted()) {
+    MEDIA_LOG(log_cb_) << "Video encryption changes not allowed.";
+    return false;
+  }
+
   // Check to see if the new config matches an existing one.
   for (size_t i = 0; i < video_configs_.size(); ++i) {
     if (config.Matches(*video_configs_[i])) {