Duplicated activity lifecycle when app is launched with screen turned OFF

Question

A. Simple scenario (closed app)

Actions to reproduce behaviour:

1. Turn off the screen
2. Run application from Android Studio (at this point no lifecycle method has been called yet)
3. Turn on the screen

Here's the launcher activity lifecycle:

// we turn on the screen

• onCreate()
• onStart()
• onResume()

// launcher activity here suddenly decides to stop and restart

• onPause() // Is this a BUG?
• onStop()
• onRestart()
• onStart()
• onResume()

B. Lock-screen scenario

Actions to reproduce behaviour:

1. Turn off the screen (you should have a lock screen)
2. Send push to your app
3. Open the lock screen and click on push notification

C. Scenario when activity was already opened

Actions to reproduce behaviour:

1. Open your app (in launcher activity)
2. Turn off the screen
3. Send push
4. Open push from lock screen

Here's the launcher activity lifecycle:

// open activity like a normal person :)

• onCreate()
• onStart()
• onResume()

// turn off the screen causes onStop(), everythin OK

• onPause()
• onStop()

// send push and click it from lock screen

• onRestart() // FIRST RESTART because we stopped activity, it's OK
• onStart()
• onResume()
• onPause() // Is this a BUG?
• onStop()
• onRestart()
• onStart()
• onResume()
• onPause()
• onStop()

Finally

This lifecycle order and restarting does not seem very reasonable to me. Does anyone have any idea why this happens?