Chromecast media pipeline: handle CENC "full sample encryption" case.

chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc

Index: chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc
diff --git a/chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc b/chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc
index 9e3de954ccb16561be7416b2602ea3d982fc9d28..c36aab9699b0eadf52c78a86371743ab99396e5f 100644
--- a/chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc
+++ b/chromecast/media/cma/ipc_streamer/decrypt_config_marshaller.cc
@@ -15,19 +15,26 @@ namespace {
 const size_t kMaxKeyIdSize = 256;
 const size_t kMaxIvSize = 256;
 const size_t kMaxSubsampleCount = 1024;
-}
 
-// static
-void DecryptConfigMarshaller::Write(
+void WriteDecryptConfigHeader(
     const ::media::DecryptConfig& config, MediaMessage* msg) {
   CHECK_GT(config.key_id().size(), 0);
   CHECK_GT(config.iv().size(), 0);
-  CHECK_GT(config.subsamples().size(), 0);
 
   CHECK(msg->WritePod(config.key_id().size()));
   CHECK(msg->WriteBuffer(config.key_id().data(), config.key_id().size()));
   CHECK(msg->WritePod(config.iv().size()));
   CHECK(msg->WriteBuffer(config.iv().data(), config.iv().size()));
+}
+
+}
+
+// static
+void DecryptConfigMarshaller::Write(
+    const ::media::DecryptConfig& config, MediaMessage* msg) {
+  CHECK_GT(config.subsamples().size(), 0);
+  WriteDecryptConfigHeader(config, msg);
+
   CHECK(msg->WritePod(config.subsamples().size()));
   for (size_t k = 0; k < config.subsamples().size(); k++) {
     CHECK(msg->WritePod(config.subsamples()[k].clear_bytes));
@@ -36,6 +43,18 @@ void DecryptConfigMarshaller::Write(
 }
 
 // static
+void DecryptConfigMarshaller::WriteFullSampleEncryption(
+    const ::media::DecryptConfig& config, int data_size, MediaMessage* msg) {
+  WriteDecryptConfigHeader(config, msg);
+  CHECK_EQ(config.subsamples().size(), 0);
+
+  // Write exactly one subsample with zero clear bytes, |data_size| cypher bytes
+  CHECK(msg->WritePod(1));
+  CHECK(msg->WritePod(0));
+  CHECK(msg->WritePod(data_size));
+}
+
+// static
 scoped_ptr< ::media::DecryptConfig> DecryptConfigMarshaller::Read(
     MediaMessage* msg) {
   size_t key_id_size = 0;