Reproduction steps:
1) Create a new project
2) Set write permission to External (SDcard)
3) Build and run application on an Android device with OS version 6.0
4) When permission request message appears - leave it as it is
5) Open Android Device Manager (located in sdk folder: /sdk/tools/monitor)
6) Select built project's process (see attached screenshot)
7) Kill that process
-- Note: this can be done via adb: with root@device/ # kill <process id>
8) If application did not crash, minimise it and open again
-- Notice, that application has crashed

Reproduced with:
2017.3.0b3, 2017.2.0f2, 2017.1.1p4, 5.6.3p4, 5.5.5f1, 5.4.6f3

Devices under testing:
Reproduced:
Samsung Galaxy S5 Neo, Android 6.0.1
Xiaomi Mi 5s, Android 6.0.1
HTC 10, Android 6.0.1
LG G4, Android 6.0.1

Unable to reproduce:
Google Pixel, Android 8.0
Samsung Galaxy S7, Android 7.0