Firebase emulator testing (#9)

- Firebase emulator added
 - Update to Espresso tests
 - Updated gradle dependencies for espresso
 - Updated config.yml
 - Updated android gradle version

.circleci/config.yml

@@ -37,17 +37,43 @@ jobs:
       # The next step will run the unit tests
       - android/run-tests:
           test-command: ./gradlew testDriverDebugUnitTest --continue
-
-#       Then start the emulator and run the Instrumentation tests!
-#       - android/start-emulator-and-run-tests:
-#           test-command: ./gradlew connectedDebugAndroidTest
-#           system-image: system-images;android-25;google_apis;x86
-
+      # Install Firebase tools needed for firebase emulator
+      - run:
+          name: Install firebase tools
+          command: |
+            curl -sL firebase.tools | bash
+      # Then start firebase emulator in the background
+      - run:
+          name: Start firebase emulator
+          command: |
+            firebase emulators:start
+          background: true
+      # Then start the emulator and run the Instrumentation tests!
+      - android/start-emulator-and-run-tests:
+          post-emulator-launch-assemble-command: ./gradlew assembleDriverDebugAndroidTest
+          test-command: ./gradlew connectedDriverDebugAndroidTest
+          system-image: system-images;android-25;google_apis;x86
       # And finally run the release build
 #      - run:
 #          name: Assemble release build
 #          command: |
 #            ./gradlew assembleDriverRelease
+      # Then publish the artifacts of the Instrumentation tests!
+      - store_artifacts:
+          path: app/build/reports/androidTests/connected
+          destination: reports
+      # Then publish the artifacts of the Firebase emulator logs!
+      - run:
+          name: save firebase emulator logs
+          command: |
+            mkdir -p tmp/firebase_logs
+            cp *.log tmp/firebase_logs
+      - store_artifacts:
+          path: tmp/firebase_logs
+          destination: logs
+      # Then publish the results of the Instrumentation tests!
+      - store_test_results:
+          path: app/build/outputs/androidTest-results/connected
 
 # Invoke jobs via workflows
 # See: https://circleci.com/docs/2.0/configuration-reference/#workflows