From: Michael Froman <mfroman@mozilla.com>
Date: Wed, 8 Oct 2025 17:49:00 +0000
Subject: Bug 1980501 - use forward class decl rather than include
 audio_state.h r?ng!

This avoids code outside of libwebrtc inadvertently including
rtc_base/containers/flat_set.h which uses c++20 features.  Once
the rest of the Mozilla tree is compiling with c++20, we can
remove this modification (see Bug 1768116).

Differential Revision: https://phabricator.services.mozilla.com/D267993
Mercurial Revision: https://hg.mozilla.org/mozilla-central/rev/9c487a574d218cc1c261b646c501db4d159754f0
---
 audio/audio_receive_stream.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/audio/audio_receive_stream.h b/audio/audio_receive_stream.h
index ef4d74f772..ff5c210dd8 100644
--- a/audio/audio_receive_stream.h
+++ b/audio/audio_receive_stream.h
@@ -34,7 +34,11 @@
 #include "api/transport/rtp/rtp_source.h"
 #include "api/units/time_delta.h"
 #include "api/units/timestamp.h"
+// This can be removed after Bug 1768116 enables
+// c++20 builds across the entire Mozilla tree.
+#if !defined(WEBRTC_MOZILLA_BUILD)
 #include "audio/audio_state.h"
+#endif
 #include "call/audio_receive_stream.h"
 #include "call/audio_state.h"
 #include "call/syncable.h"
@@ -47,6 +51,14 @@ class PacketRouter;
 class RtpStreamReceiverControllerInterface;
 class RtpStreamReceiverInterface;
 
+// This can be removed after Bug 1768116 enables
+// c++20 builds across the entire Mozilla tree.
+#if defined(WEBRTC_MOZILLA_BUILD)
+namespace internal {
+class AudioState;
+}
+#endif
+
 namespace voe {
 class ChannelReceiveInterface;
 }  // namespace voe