Steps to reproduce:
1. Open user attached project "OrientationCrash.zip" with a Unity pro license
2. Build and run on android
3. Have phone/tablet in landscape mode before app launches
4. When splash screen is showing flip the device into portrait mode
5. After splash screen ends app should crash

Expected: Custom splash screen should not cause a crash when you re-orient
Actual: App crashes after you reorient and splash screen ends

Reproduced on: 2018.1.0a5, 2017.3.0b10, 2017.2.0p3, 2017.1.2p3, 5.6.4p3

Note: Splash screen on 5.5 would just flicker the image once and not show it anymore during the load.
Devices Under Test:

Repro:
Samsung SM T533*, OS:5.1.1, CPU:armeabi-v7a, GPU:Adreno (TM) 306, Build:samsung/matissevewifixx/matissevewifi:5.1.1/LMY47X/T533XXS1BPL2:user/release-keys

Amazon KFFOWI (Fire (2015))*, OS:5.1.1, CPU:armeabi-v7a, GPU:Mali-450 MP, Build:Amazon/full_ford/ford:5.1.1/LMY47O/37.5.4.2_user_542169020:user/release-keys

No Repro:

Verizon SM G930V*, OS:6.0.1, CPU:arm64-v8a, GPU:Adreno (TM) 530, Build:Verizon/heroqltevzw/heroqltevzw:6.0.1/MMB29M/G930VVRU2APG3:user/release-keys

Samsung SM P600 (Galaxy Note 10.1)*, OS:5.1.1, CPU:armeabi-v7a, GPU:Mali-T628, Build:samsung/lt03wifixx/lt03wifi:5.1.1/LMY47X/P600XXUDQA1:user/release-keys

Htc HTC 10*, OS:7.0, CPU:arm64-v8a, GPU:Adreno (TM) 530, Build:htc/pmeuhl_00401/htc_pmeuhl:7.0/NRD90M/857212.41:user/release-keys

Samsung GT I9105P (Galaxy S2+)*, OS:4.2.2, CPU:armeabi-v7a, GPU:VideoCore IV HW, Build:samsung/s2vepxx/s2vep:4.2.2/JDQ39/I9105PXXUBNG1:user/release-keys

Amazon KFSAWA*, OS:5.1.1, CPU:armeabi-v7a, GPU:Adreno (TM) 420, Build:Amazon/saturn/saturn:5.1.1/LVY48F/22.5.7.0_user_570208620:user/release-keys