Support HLS MPEG2 TS with SAMPLE-AES encryption.

media/media_options.gni

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/chromecast_build.gni")
 import("//build/config/features.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 
 declare_args() {
   # Allows distributions to link pulseaudio directly (DT_NEEDED) instead of
@@ skipping 32 matching lines @@
 
   # Enable support for the 'cbcs' encryption scheme added by MPEG Common
   # Encryption 3rd Edition (ISO/IEC 23001-7), published 02/15/2016.
   enable_cbcs_encryption_scheme = is_chromecast
 
   # Enable HEVC/H265 demuxing. Actual decoding must be provided by the
   # platform. Enable by default for Chromecast.
   enable_hevc_demuxing = proprietary_codecs && is_chromecast
 
   enable_webrtc = !is_ios
+
+  # Enable HLS with SAMPLE-AES decryption.
+  # Enabled by default on the cast desktop implementation to allow unit tests of
+  # MP2TS parsing support.
+  enable_hls_sample_aes = proprietary_codecs && is_cast_desktop_build
 }
 
+# enable_hls_sample_aes can only be true if enable_mse_mpeg2ts_stream_parser is.
+assert(enable_mse_mpeg2ts_stream_parser || !enable_hls_sample_aes)
+
 # Use a second declare_args() to pick up possible overrides of |use_cras|.
 declare_args() {
   # Enables runtime selection of PulseAudio library.
   use_pulseaudio = false
 
   # Enables runtime selection of ALSA library for audio.
   use_alsa = false
 
   # Alsa should be used on non-Android, non-Mac POSIX systems.
   # Alsa should be used on desktop Chromecast and audio-only Chromecast builds.
@@ skipping 64 matching lines @@
     }
   }
 }
 
 declare_args() {
   # This switch defines whether the Media Remoting implementation will be built.
   # When enabled, media is allowed to be renderer and played back on remote
   # devices when the tab is being casted and other conditions are met.
   enable_media_remoting = !is_chromecast && !is_ios && !is_android
 }