To Reproduce:

1. Build the attached project for GLES2 (tested on iOS)
2. Observe that after the app is launched you'll get these errors:

-------- Shader compilation failed
#version 100
precision mediump float;

[... shader code...]

-------- failed compiling:
fragment evaluation shader
Note: Creation of internal variant of shader 'Hidden/CubeBlend' failed.
WARNING: Shader Unsupported: 'Hidden/CubeBlend' - Pass '' has no vertex shader

(same with some other shaders in the project - "GroundShader" etc..)

Same shaders compiles fine with Metal & GLES3 on trunk and with GLES2, on older builds, like 5.3.2f1.