Do not attempt to receive IPv6 flow labels on Android since
the setsockopt call always fails.

PiperOrigin-RevId: 713714235

quiche/quic/core/quic_udp_socket_posix.inc

diff --git a/quiche/quic/core/quic_udp_socket_posix.inc b/quiche/quic/core/quic_udp_socket_posix.inc
index c368f2b..88bdf86 100644
--- a/quiche/quic/core/quic_udp_socket_posix.inc
+++ b/quiche/quic/core/quic_udp_socket_posix.inc
@@ -235,7 +235,7 @@
                                    << "IPv6 socket";
       return false;
     }
-#if defined(__linux__)
+#if defined(__linux__) && !defined(__ANDROID__)
     if (GetQuicRestartFlag(quic_support_flow_label2)) {
       QUIC_RESTART_FLAG_COUNT_N(quic_support_flow_label2, 5, 6);
       if (setsockopt(fd, SOL_IPV6, IPV6_FLOWINFO, &set, sizeof(set)) != 0) {

quiche/quic/core/quic_udp_socket_test.cc

diff --git a/quiche/quic/core/quic_udp_socket_test.cc b/quiche/quic/core/quic_udp_socket_test.cc
index d1af818..6417c0e 100644
--- a/quiche/quic/core/quic_udp_socket_test.cc
+++ b/quiche/quic/core/quic_udp_socket_test.cc
@@ -119,7 +119,14 @@
   do {
     socket_api.ReadPacket(server_socket, packet_info_interested, &read_result);
   } while (!read_result.ok);
+#if !defined(__ANDROID__)
+  ASSERT_TRUE(
+      read_result.packet_info.HasValue(QuicUdpPacketInfoBit::V6_FLOW_LABEL));
   EXPECT_EQ(client_flow_label, read_result.packet_info.flow_label());
+#else
+  EXPECT_FALSE(
+      read_result.packet_info.HasValue(QuicUdpPacketInfoBit::V6_FLOW_LABEL));
+#endif
 
   const uint32_t server_flow_label = 3;
   packet_info.SetPeerAddress(client_address);
@@ -132,7 +139,14 @@
   do {
     socket_api.ReadPacket(client_socket, packet_info_interested, &read_result);
   } while (!read_result.ok);
+#if !defined(__ANDROID__)
+  ASSERT_TRUE(
+      read_result.packet_info.HasValue(QuicUdpPacketInfoBit::V6_FLOW_LABEL));
   EXPECT_EQ(server_flow_label, read_result.packet_info.flow_label());
+#else
+  EXPECT_FALSE(
+      read_result.packet_info.HasValue(QuicUdpPacketInfoBit::V6_FLOW_LABEL));
+#endif
 }
 
 }  // namespace