gitlab-ci: only run Espresso tests if KVM is available

The emulators without KVM are just too slow to reliably run the Espresso
tests, at least with the timeouts that are set by default.

.gitlab-ci.yml

@@ -74,7 +74,9 @@ errorprone:
     - wait-for-emulator
     - adb devices
     - adb shell input keyevent 82 &
-    - test $AVD_SDK -ge 25 || export FLAG=-Pandroid.testInstrumentationRunnerArguments.notAnnotation=android.support.test.filters.LargeTest
+    - if [ $AVD_SDK -lt 25 ] || ! emulator -accel-check; then
+          export FLAG=-Pandroid.testInstrumentationRunnerArguments.notAnnotation=android.support.test.filters.LargeTest;
+      fi
     - ./gradlew connectedFullDebugAndroidTest $FLAG
       || ./gradlew connectedFullDebugAndroidTest $FLAG
       || ./gradlew connectedFullDebugAndroidTest $FLAG