Bug 1646838: Rewrite this to use c++ structured bindings, and pick better names. r=mjf

Depends on D80275

Differential Revision: https://phabricator.services.mozilla.com/D80277

media/webrtc/signaling/src/jsep/JsepSessionImpl.cpp

@@ -926,14 +926,13 @@ nsresult JsepSessionImpl::HandleNegotiatedSession(
   NS_ENSURE_SUCCESS(rv, rv);
 
   // First, set the bundle level on the transceivers
-  for (auto& midAndMaster : bundledMids) {
-    JsepTransceiver* bundledTransceiver =
-        GetTransceiverForMid(midAndMaster.first);
+  for (auto& [mid, transportOwner] : bundledMids) {
+    JsepTransceiver* bundledTransceiver = GetTransceiverForMid(mid);
     if (!bundledTransceiver) {
-      JSEP_SET_ERROR("No transceiver for bundled mid " << midAndMaster.first);
+      JSEP_SET_ERROR("No transceiver for bundled mid " << mid);
       return NS_ERROR_INVALID_ARG;
     }
-    bundledTransceiver->SetBundleLevel(midAndMaster.second->GetLevel());
+    bundledTransceiver->SetBundleLevel(transportOwner->GetLevel());
   }
 
   // Now walk through the m-sections, perform negotiation, and update the

media/webrtc/signaling/src/sdp/SdpHelper.h

@@ -42,7 +42,7 @@ class SdpHelper {
   bool MsectionIsDisabled(const SdpMediaSection& msection) const;
   static void DisableMsection(Sdp* sdp, SdpMediaSection* msection);
 
-  // Maps each mid to the m-section that is the master of its bundle.
+  // Maps each mid to the m-section that owns its bundle transport.
   // Mids that do not appear in an a=group:BUNDLE do not appear here.
   typedef std::map<std::string, const SdpMediaSection*> BundledMids;