language: android
android:
  components:
    - platform-tools
    - build-tools-26.0.0
    - android-26
    - extra-android-m2repository
script:
  - sh gradlew build
branches:
  only:
    - master

language: android
android:
  components:
    - platform-tools
    - build-tools-26.0.0
    - android-26
    - extra-android-m2repository
script:
  - bash gradlew build
branches:
  only:
    - master

Use bash to start gradlew
Use bash to start gradlew

Just `sh` doesn't work for Travis ...
