media config: expand is_encrypted to a struct.

media/base/audio_decoder_config.h

Index: media/base/audio_decoder_config.h
diff --git a/media/base/audio_decoder_config.h b/media/base/audio_decoder_config.h
index ae72383a0a99853cb13bf6d744c120b3474b4f97..d098a9480fb167490040eb582e0ff9d6d149d88b 100644
--- a/media/base/audio_decoder_config.h
+++ b/media/base/audio_decoder_config.h
@@ -11,6 +11,7 @@
 #include "base/basictypes.h"
 #include "base/time/time.h"
 #include "media/base/channel_layout.h"
+#include "media/base/encryption_scheme.h"
 #include "media/base/media_export.h"
 #include "media/base/sample_format.h"
 
@@ -61,7 +62,7 @@ class MEDIA_EXPORT AudioDecoderConfig {
                      ChannelLayout channel_layout,
                      int samples_per_second,
                      const std::vector<uint8_t>& extra_data,
-                     bool is_encrypted);
+                     const EncryptionScheme& encryption_scheme);
 
   ~AudioDecoderConfig();
 
@@ -71,7 +72,7 @@ class MEDIA_EXPORT AudioDecoderConfig {
                   ChannelLayout channel_layout,
                   int samples_per_second,
                   const std::vector<uint8>& extra_data,
-                  bool is_encrypted,
+                  const EncryptionScheme& encryption_scheme,
                   base::TimeDelta seek_preroll,
                   int codec_delay);
 
@@ -106,7 +107,12 @@ class MEDIA_EXPORT AudioDecoderConfig {
   // Whether the audio stream is potentially encrypted.
   // Note that in a potentially encrypted audio stream, individual buffers
   // can be encrypted or not encrypted.
-  bool is_encrypted() const { return is_encrypted_; }
+  bool is_encrypted() const { return encryption_scheme_.is_encrypted(); }

[ddorwin, 2015/12/10 18:36:00]

As mentioned earlier, I think this might be hiding tests that we should update
to check encryption_scheme().

[ddorwin, 2015/12/10 18:36:00]

Again, unclear if this is a "simple accessor."

[dougsteed, 2015/12/14 21:19:01]

I don't know all the usages of this class, and I don't want to impose fresh
requirements on tests for components that are not adding support for CBC
(CENCv3). So my philosophy was to not add any additional constraints on such
unaffected classes and tests. If all they are interested in is a boolean
"is_encrypted", then they can more or less continue to use EncryptionScheme as
if it was a boolean.

+
+  // Encryption scheme used for encrypted buffers.
+  const EncryptionScheme& encryption_scheme() const {
+    return encryption_scheme_;
+  }
 
  private:
   AudioCodec codec_;
@@ -116,7 +122,7 @@ class MEDIA_EXPORT AudioDecoderConfig {
   int samples_per_second_;
   int bytes_per_frame_;
   std::vector<uint8_t> extra_data_;
-  bool is_encrypted_;
+  EncryptionScheme encryption_scheme_;
 
   // |seek_preroll_| is the duration of the data that the decoder must decode
   // before the decoded data is valid.