Merge #15022: tests: Upgrade Travis OS to Xenial

b6f0db69a9 Increase timeout of featuer_assumevalid test to fix flaky tests (Graham Krizek)
aa9aca85f1 If tests are ran with (ASan + LSan), Docker needs access to ptrace (Graham Krizek)
a3b8b43663 Update Travis base OS to Xenial (Graham Krizek)

Pull request description:

  Update base Travis OS to `xenial` from `trusty`.

  Link to Travis Docs for Xenial: https://docs.travis-ci.com/user/reference/xenial/

  As noted in the documentation, Docker version is also updated from `17.06` to `18.06`

  Also includes:
      - If running Bitcoin config with LSan sanitizer, Allow ptrace in Docker run command
      - Increase timeout of feature_assumevalid test to fix flaky tests

Tree-SHA512: baf2eda0cbb9990c43c76de1aebc8dd4a3f540323ac1fe2e164ac3bcf1fe3afa3e5b026bfeb5d650dae09a6854695d5744c1130c2fa82ece86c6835ba152f68d

.travis.yml

@@ -1,4 +1,4 @@
-dist: trusty
+dist: xenial
 os: linux
 language: minimal
 cache:

.travis/test_04_install.sh

@@ -15,6 +15,8 @@ export UBSAN_OPTIONS="suppressions=${TRAVIS_BUILD_DIR}/test/sanitizer_suppressio
 env | grep -E '^(BITCOIN_CONFIG|CCACHE_|WINEDEBUG|LC_ALL|BOOST_TEST_RANDOM|CONFIG_SHELL|(ASAN|LSAN|TSAN|UBSAN)_OPTIONS)' | tee /tmp/env
 if [[ $HOST = *-mingw32 ]]; then
   DOCKER_ADMIN="--cap-add SYS_ADMIN"
+elif [[ $BITCOIN_CONFIG = *--with-sanitizers=*address* ]]; then # If ran with (ASan + LSan), Docker needs access to ptrace (https://github.com/google/sanitizers/issues/764)
+  DOCKER_ADMIN="--cap-add SYS_PTRACE"
 fi
 DOCKER_ID=$(docker run $DOCKER_ADMIN -idt --mount type=bind,src=$TRAVIS_BUILD_DIR,dst=$TRAVIS_BUILD_DIR --mount type=bind,src=$CCACHE_DIR,dst=$CCACHE_DIR -w $TRAVIS_BUILD_DIR --env-file /tmp/env $DOCKER_NAME_TAG)
 

test/functional/feature_assumevalid.py

@@ -180,7 +180,7 @@ class AssumeValidTest(BitcoinTestFramework):
         for i in range(2202):
             p2p1.send_message(msg_block(self.blocks[i]))
         # Syncing 2200 blocks can take a while on slow systems. Give it plenty of time to sync.
-        p2p1.sync_with_ping(120)
+        p2p1.sync_with_ping(150)
         assert_equal(self.nodes[1].getblock(self.nodes[1].getbestblockhash())['height'], 2202)
 
         # Send blocks to node2. Block 102 will be rejected.