Fix quic_frames_test when QUIC_FRAME_DEBUG is defined.

PiperOrigin-RevId: 716227585

quiche/quic/core/frames/quic_frame.cc

diff --git a/quiche/quic/core/frames/quic_frame.cc b/quiche/quic/core/frames/quic_frame.cc
index 3353326..7a64538 100644
--- a/quiche/quic/core/frames/quic_frame.cc
+++ b/quiche/quic/core/frames/quic_frame.cc
@@ -112,7 +112,8 @@
       frame->type != WINDOW_UPDATE_FRAME && frame->type != BLOCKED_FRAME &&
       frame->type != STOP_SENDING_FRAME &&
       frame->type != PATH_CHALLENGE_FRAME &&
-      frame->type != PATH_RESPONSE_FRAME) {
+      frame->type != PATH_RESPONSE_FRAME &&
+      frame->type != IMMEDIATE_ACK_FRAME) {
     QUICHE_CHECK(!frame->delete_forbidden) << *frame;
   }
 #endif  // QUIC_FRAME_DEBUG