How to reproduce:
1. Connect a device which doesn't recognise your machine (or in Developer Options select revoke USB debugging authorizations)
2. You will get a popup in device "Allow USB debugging", click Cancel or leave popup open
3. Create a new project
4. It uses Standalone Platform, Open Build Settings and select Android Platform
Result: error in the console
5. Switch to Android platform
Result: you get the same error again

CommandInvokationFailure: Unable to retrieve device properties. Please make sure the Android SDK is installed and is properly configured in the Editor. See the Console for more details.
/Users/ieva/Library/Android/sdk/platform-tools/adb -s "UBV0218412000859" shell getprop

stderr[
error: device unauthorized.
This adb server's $ADB_VENDOR_KEYS is not set
Try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.

Reproducible: 2018.1.9f2, 2018.2.9f1, 2018.3.0a4, 2018.3.0b6, 2019.1.0a1, 2019.1.0a5
Not reproducible: 2017.4.12f1

Tried and reproduce: Xiaomi Mi 5
Tried and didn't reproduce: iPhone XS Max device which didn't Trust the computer

Note: Project can be successfully built, so this issue is minor