Add never_timeout_connection field to OutputStreamParams proto

If set to true, mixer inactivity timer is not started, preventing the
mixer from dropping connection after kInactivityTimeout of no incoming
data.

Bug: b/138551750
Change-Id: Iacf3327a0b185e76d0976d2bc50a6a0b95de942b
Merge-With: eureka-internal/343509
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1960318Reviewed-by: Kenneth MacKay <kmackay@chromium.org>
Commit-Queue: Marcin Radomski <dextero@google.com>
Auto-Submit: Marcin Radomski <dextero@google.com>
Cr-Commit-Position: refs/heads/master@{#724567}

chromecast/media/audio/mixer_service/mixer_service.proto

@@ -55,6 +55,10 @@ message OutputStreamParams {
 
   // If |true|, this stream will not be included in the mixer's stream counts.
   optional bool ignore_for_stream_count = 14;
+
+  // If |true|, the receiver will not close the stream after a period of
+  // inactivity.
+  optional bool never_timeout_connection = 15;
 }
 
 // Indicates that we want to start playing the sample with PTS |start_pts|

chromecast/media/cma/backend/mixer/mixer_input_connection.cc

@@ -171,6 +171,7 @@ MixerInputConnection::MixerInputConnection(
       io_task_runner_(base::ThreadTaskRunnerHandle::Get()),
       max_queued_frames_(std::max(GetQueueSize(params), algorithm_fill_size_)),
       start_threshold_frames_(GetStartThreshold(params)),
+      never_timeout_connection_(params.never_timeout_connection()),
       fader_(this,
              params.has_fade_frames()
                  ? params.fade_frames()
@@ -371,6 +372,10 @@ void MixerInputConnection::OnConnectionError() {
 }
 
 void MixerInputConnection::OnInactivityTimeout() {
+  if (never_timeout_connection_) {
+    return;
+  }
+
   LOG(INFO) << "Timed out " << this << " due to inactivity";
   OnConnectionError();
 }

chromecast/media/cma/backend/mixer/mixer_input_connection.h

@@ -156,6 +156,7 @@ class MixerInputConnection : public mixer_service::MixerSocket::Delegate,
 
   // Only used on the IO thread.
   bool audio_ready_for_playback_fired_ = false;
+  bool never_timeout_connection_ = false;
   base::OneShotTimer inactivity_timer_;
   bool connection_error_ = false;
   int buffer_pool_frames_ = 0;