On the other hand we have Robolectric gradle plugin which as documentation says:
A Gradle plugin which enables Robolectric tests.
This plugin piggy-backs on the unit testing support added in version 1.1.0 of the Android Gradle plugin and configures the test tasks to work correctly with Robolectric.
I wonder why in Robolectric sample project there is no sign of Robolectric Gradle Plugin.
If we can run robolectric tests without the plugin in Android Studio using gradle wrapper, then what is the exact usages of Plugin?