Fix VideoSendStreamImpl::OnPacketFeedbackError: operator precedence.

in:
if (auto it = some_set.find(some_value) != some_set.end()) {}

"it" is bool, not an iterator.

Bug: webrtc:9652
Change-Id: Icfaab685f4e2f4456e24d5a14b11309dddfdc0fe
Reviewed-on: https://webrtc-review.googlesource.com/84420
Commit-Queue: Benoit Lize <lizeb@chromium.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24389}
diff --git a/video/video_send_stream_impl.cc b/video/video_send_stream_impl.cc
index 0c15856..cf4bf87 100644
--- a/video/video_send_stream_impl.cc
+++ b/video/video_send_stream_impl.cc
@@ -709,8 +709,8 @@
   }
   // Lost feedbacks are not considered to be lost packets.
   for (const PacketFeedback& packet : packet_feedback_vector) {
-    if (auto it = feedback_packet_seq_num_set_.find(packet.sequence_number) !=
-                  feedback_packet_seq_num_set_.end()) {
+    auto it = feedback_packet_seq_num_set_.find(packet.sequence_number);
+    if (it != feedback_packet_seq_num_set_.end()) {
       const bool lost = packet.arrival_time_ms == PacketFeedback::kNotReceived;
       loss_mask_vector_.push_back(lost);
       feedback_packet_seq_num_set_.erase(it);