Reproduction steps:
1. Open "swagger-il2cpp.zip" project
2. Build & Run for Android with Mono Scripting Backend
3. Press the "Status" button and note the result (SUCCESS)
4. Build & Run for Android with IL2CPP Scripting Backend
5. Press the "Status" button and note the result (FAILED)

Expected Result: Scripts work in builds using IL2CPP, just like Mono
Actual Result: Scripts don't work with IL2CPP

Reproduced with: 2020.1.0a3, 2019.3.0b2, 2019.2.4f1, 2019.1.14f1, 2019.1.9f1, 2018.4.8f1
Could not reproduce on: 2017.4.32f1 (Request doesn't get a either response, timeout)

Note:
Reproduces with .NET 4.x Equivalent (.NET Standard 2.0 and .NET 4.x)

Repro Devices:
iPhone 8 Plus (iOS 12.0)
VLNQA00013, Samsung Galaxy S6 edge+ (SM-G928F), Android 7.0, CPU: Exynos 7 Octa 7420, GPU: Mali-T760
VLNQA00002, Samsung Galaxy S5 Neo (SM-G903F), Android 6.0.1, CPU: Exynos 7 Octa 7580, GPU: Mali-T720
VLNQA00224, Samsung Galaxy A5(2017) (SM-A520F), Android 8.0.0, CPU: Exynos 7 Octa 7880, GPU: Mali-T830
VLNQA00022, Xiaomi Redmi Note 3 (Redmi Note 3), Android 5.1.1, CPU: Snapdragon 617 MSM8952, GPU: Adreno (TM) 510
VLNQA00115, Sony Xperia Z3 (D6603), Android 6.0.1, CPU: Snapdragon 801 MSM8974AC, GPU: Adreno (TM) 330
VLNQA00123, Google Pixel 2 XL (Pixel 2 XL), Android 9, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540
VLNQA00017, Huawei Nexus 6P (Nexus 6P), Android 8.0.0, CPU: Snapdragon 810 MSM8994, GPU: Adreno (TM) 430
VLNQA00262, Sony Xperia XZ Premium (G8141), Android 9, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540
VLNQA00272, Samsung Galaxy S10+ (SM-G975U), Android 9, CPU: Snapdragon 855 SM8150, GPU: Adreno (TM) 640
VLNQA00078, Motorola Nexus 6 (Nexus 6), Android 7.1.1, CPU: Snapdragon 805 APQ8084AB, GPU: Adreno (TM) 420
VLNQA00052, Xiaomi MI MAX (MI MAX), Android 7.0, CPU: Snapdragon 617 MSM8952, GPU: Adreno (TM) 510
VLNQA00015, Samsung Galaxy Note8 (SM-N950W), Android 8.0.0, CPU: Snapdragon 835 MSM8998, GPU: Adreno (TM) 540