Fix T77686: EEVEE environment pass with film transparency

When the film is set to transparent the environment pass should still be
rendered solid. otherwise it renders black.

Reviewed By: Clément Foucault

Differential Revision: https://developer.blender.org/D8046

source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl

@@ -94,6 +94,7 @@ layout(std140) uniform renderpass_block
   bool renderPassGlossyLight;
   bool renderPassEmit;
   bool renderPassSSSColor;
+  bool renderPassEnvironment;
 };
 
 vec3 render_pass_diffuse_mask(vec3 diffuse_color, vec3 diffuse_light)