COMP: Block tests when VTK_USE_GLSL_SHADERS Off

Some tests require VTK_USE_GLSL_SHADERS On. Block them if off.

Change-Id: I5c3e689aef5b09fd5e8d37001a25af1685fd3673
Merge topic 'GlslShaderGuard' into master

fc372ce6 COMP: Block tests when VTK_USE_GLSL_SHADERS Off