Add decoder-specific settings with proper lifetime.

webrtc/config.h

Index: webrtc/config.h
diff --git a/webrtc/config.h b/webrtc/config.h
index b2dfe2d272642fa5b8f73bd4a0e75b4a3c4925d1..6371b4f42f64292a9988a0896cc30f9611501fb0 100644
--- a/webrtc/config.h
+++ b/webrtc/config.h
@@ -16,6 +16,9 @@
 #include <string>
 #include <vector>
 
+#include "webrtc/base/optional.h"
+#include "webrtc/base/refcount.h"
+#include "webrtc/base/scoped_ref_ptr.h"

[sprang_webrtc, 2016/07/27 08:37:25]

Not sure what the current policy is regarding importing utility classes into the
base api, as doing that may result in changes to those utilities breaking
external applications. Especially worried about scoped_ref_ptr. Would've been
nice with more support for stl here :/

 #include "webrtc/common.h"
 #include "webrtc/common_types.h"
 #include "webrtc/typedefs.h"
@@ -146,6 +149,20 @@ struct VideoEncoderConfig {
   bool expect_encode_from_texture;
 };
 
+struct VideoDecoderH264extraSettings {
+  std::string spropParameterSets;
+};
+
+// These are reference counted to permit copying VideoDecoderConfig and be
+// kept alive until all decoder_specific_settings go out of scope.
+//
+class DecoderSpecificSettings : public rtc::RefCountInterface {
+ public:
+  virtual ~DecoderSpecificSettings() {}
+  rtc::Optional<VideoDecoderH264extraSettings> h264_extra_settings;
+  // vp8_extra_settings, and vp9_extra_settings will be added when required
+};

[sprang_webrtc, 2016/07/27 08:37:25]

If we're using an Optional for each codec, I'm not sure we really need the
refcounting (assuming copyable extras)?

+
 // Controls the capacity of the packet buffer in NetEq. The capacity is the
 // maximum number of packets that the buffer can contain. If the limit is
 // exceeded, the buffer will be flushed. The capacity does not affect the actual