java.lang.IllegalArgumentException: dexcache == null (and no default could be found; consider setting the 'dexmaker.dexcache' system property)
at com.google.dexmaker.DexMaker.generateAndLoad(DexMaker.java:359)

public class CustomInstrumentationTestRunner extends InstrumentationTestRunner {

    @Override public void onCreate (final Bundle arguments) {
        super.onCreate(arguments);

        // temporary workaround for an incompatibility in current dexmaker (1.1) implementation and Android >= 4.3
        // cf. https://code.google.com/p/dexmaker/issues/detail?id=2 for details
        System.setProperty("dexmaker.dexcache", getTargetContext().getCacheDir().toString());
    }
}

android {
    defaultConfig {
        testInstrumentationRunner "your.package.CustomInstrumentationTestRunner"
    }
}