Skip tests which need an IPv6 address on Cuttlefish.

Avoids:

android.net.cts.DnsTest#testDnsWorks: FAILED (4.993s)

STACKTRACE:
java.lang.AssertionError: Default network did not provide IPv6 connectivity after 5000ms. Please connect to an IPv6-capable network.
lp={InterfaceName: wlan0 LinkAddresses: [ fe80::6c1f:76ff:fe50:2c84/64,192.168.99.115/25 ] DnsAddresses: [ /192.168.99.1 ] Domains: l
an MTU: 0 ServerAddress: /192.168.99.1 TcpBufferSizes: 524288,1048576,2097152,262144,524288,1048576 Routes: [ fe80::/64 -> :: wlan0 m
tu 0,192.168.99.0/25 -> 0.0.0.0 wlan0 mtu 0,0.0.0.0/0 -> 192.168.99.1 wlan0 mtu 0 ]}
  at org.junit.Assert.fail(Assert.java:89)
  at org.junit.Assert.assertTrue(Assert.java:42)
  at android.net.cts.DnsTest.ensureIpv6Connectivity(DnsTest.java:319)
  at android.net.cts.DnsTest.testDnsWorks(DnsTest.java:90)

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I4b94edae6d196ca02858702dec40ee2bad1db494
1 file changed