Updated travis ci without emulator

Author: gauravk95

.travis.yml

@@ -1,30 +1,24 @@
 language: android
 
+# setup before install
 before_install:
     - echo yes | android update sdk --filter extra-android-support --no-ui --force > /dev/null
     - echo yes | android update sdk --filter extra-android-m2repository --no-ui --force > /dev/null
     - chmod +x ./gradlew
     - cp local.properties.ci local.properties
 
+# define android packages and licenses
 android:
   components:
     - tools
     - platform-tools
     - build-tools-27.0.3
     - android-27
-    - android-22
-    - sys-img-armeabi-v7a-android-22
     - extra-android-m2repository
 
   licenses:
     - android-sdk-license-.+
 
-before_script:
-  # Create and start emulator
-  - echo no | android create avd --force -n test -t android-22 --abi armeabi-v7a
-  - emulator -avd test -no-skin -no-audio -no-window &
-  - android-wait-for-emulator
-  - adb shell input keyevent 82 &
-
+# only perform unit test only
 script:
-    - ./gradlew connectedAndroidTest
+    - ./gradlew test