Change --quic_bbr2_default_inflight_hi_headroom from 0.01 to 0.15.

PiperOrigin-RevId: 341845614
Change-Id: Ie9dce8ac90426183e12d5b24dd9439132bd7e3f1

quic/core/quic_protocol_flags_list.h

diff --git a/quic/core/quic_protocol_flags_list.h b/quic/core/quic_protocol_flags_list.h
index 9484a23..b9d0a2d 100644
--- a/quic/core/quic_protocol_flags_list.h
+++ b/quic/core/quic_protocol_flags_list.h
@@ -162,7 +162,7 @@
 QUIC_PROTOCOL_FLAG(
     double,
     quic_bbr2_default_inflight_hi_headroom,
-    0.01,
+    0.15,
     "The default fraction of unutilized headroom to try to leave in path "
     "upon high loss.")