This patch adds the link validations on the uniforms defined in a
geometry shader.

1. Validate if there is any link mismatch between a geometry shader
   uniform and a uniform defined in another shader in the current
   graphics pipeline.
2. Validate if the number of images, samplers or atomic counters in
   a geometry shader exceeds the related resource limit.
3. Validate if there is name contradiction between a geometry shader
   uniform and a vertex shader attribute.

BUG=angleproject:1941
TEST=dEQP-GLES31.functional.shaders.linkage.es31.geometry.uniform.*
     dEQP-GLES31.functional.geometry_shading.basic.*
     dEQP-GLES31.functional.geometry_shading.conversion.*
     dEQP-GLES31.functional.geometry_shading.emit.*
     dEQP-GLES31.functional.geometry_shading.varying.*
     dEQP-GLES31.functional.geometry_shading.instanced.geometry_*
     dEQP-GLES31.functional.geometry_shading.instanced.invocation_output_*
     dEQP-GLES31.functional.geometry_shading.instanced.draw_*

Change-Id: I365aee624a3a79658c3e4c7487a586cf9532b529
Reviewed-on: https://chromium-review.googlesource.com/939264
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>