Godot: All materials are extremely reflective on android

[Tobi-La]

Godot version:
3.2.dev.calinou.a25e52fb7

OS/device including version:

Android, Tested on Samsung Galaxy J5 duos + Oukitel K6000 pro GLES2

Issue description:
It seems all materials are extremely reflections on the current master build on Android.

Herre is how a basic scene looks on 3.1.1 stable:

And here on the master build 3.2.dev.calinou.a25e52fb7

Steps to reproduce:

• Create a basic scene with a few meshes and a directional light source and run in on android

Minimal reproduction project:
ReflectiveMaterials.zip

[mbrlabs]

Same here with Galaxy S8, Android 9 and GLES2 Backend.
I tracked the issue down to commit 5c252092e17a563b54b9c9bcb88127af102926e2 (#27898).
@clayjohn could you have a look?

[lawnjelly]

I may have had this issue too, so far I have been fixing by turning off the checkbox 'Force Vertex Shading.mobile', which may be a workaround until it gets fixed (albeit more expensive shaders).

[mbrlabs]

That workaround produces the expected result. I just noticed that you can reproduce this issue on desktop as well if you check "Force Vertex shading"

[clayjohn]

@mbrlabs I'll take a look!