Fix short-circuit evaluation in RollbackTransports

This prevents Use-After-Free by ensuring all map_change_callback_
invocations occur during rollback, even if one fails.

Bug: chromium:504597736
Change-Id: If5dd44bcdec27d06af18fc74c526264ab08ae9d1
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/465880
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Auto-Submit: Tomas Gunnarsson <tommi@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#47513}

pc/jsep_transport_collection.cc

diff --git a/pc/jsep_transport_collection.cc b/pc/jsep_transport_collection.cc
index 6d8dbf0..3c469ff 100644
--- a/pc/jsep_transport_collection.cc
+++ b/pc/jsep_transport_collection.cc
@@ -269,14 +269,16 @@
   // First, remove any new mid->transport mappings.
   for (const auto& kv : mid_to_transport_) {
     if (stable_mid_to_transport_.count(kv.first) == 0) {
-      ret = ret && map_change_callback_(kv.first, nullptr);
+      bool success = map_change_callback_(kv.first, nullptr);
+      ret = ret && success;
     }
   }
   // Next, restore old mappings.
   for (const auto& kv : stable_mid_to_transport_) {
     auto it = mid_to_transport_.find(kv.first);
     if (it == mid_to_transport_.end() || it->second != kv.second) {
-      ret = ret && map_change_callback_(kv.first, kv.second);
+      bool success = map_change_callback_(kv.first, kv.second);
+      ret = ret && success;
     }
   }
   mid_to_transport_ = stable_mid_to_transport_;