Try to fix travis build

.travis.yml

@@ -1,15 +1,18 @@
 language: dart
 dart:
-  - "1.23.0"
-with_content_shell: true
+  - "1.24.2"
+dart_task:
+  - test: --platform vm
+  - test: --platform content_shell
+    install_dartium: true
 before_install:
   - export DISPLAY=:99.0
-  - ./tool/setup_dartium.sh
-  - export PATH=$PATH":$PWD"
-  - sh -e /etc/init.d/xvfb start
-  - sleep 3 # give xvfb some time to start
+#  - ./tool/setup_dartium.sh
+#  - export PATH=$PATH":$PWD"
+#  - sh -e /etc/init.d/xvfb start
+#  - sleep 3 # give xvfb some time to start
 script:
   - pub run dart_dev analyze
-  - pub run dart_dev test --integration
+#  - pub run dart_dev test --integration
   - ./tool/generate_coverage.sh
   - bash <(curl -s https://codecov.io/bash) -f coverage/coverage.lcov