Only check for active targets in GetTargetIds (#5275)

Author: Brian Chen

Firestore/core/src/firebase/firestore/remote/remote_event.cc

@@ -200,9 +200,10 @@ std::vector<TargetId> WatchChangeAggregator::GetTargetIds(
   }
 
   std::vector<TargetId> result;
-  result.reserve(target_states_.size());
   for (const auto& entry : target_states_) {
-    result.push_back(entry.first);
+    if (IsActiveTarget(entry.first)) {
+      result.push_back(entry.first);
+    }
   }
 
   return result;