android-942
Developing infrastucture for launching integration tests and unit tests for Android. Porting integration tests and indexer tests on Android platform.
Several explicit constructors per the Cppcheck report.
Fixing unit and integration test for Android.
[android] Updated gradle to 5.1.1 and studio to 3.4.1
[android] Migrate to android-ndk-12x
Merge remote-tracking branch 'origin/run_android_tests' into squashed_android_tests