It is invalid if the same decoration is applied to the same id multiple
times. This adds a check before adding a decoration that the decoration
is not already in the list. If it is, then the duplicate is not added.
Fixes#3627
This introduces five new "Validation failures":
- baseResults/hlsl.semantic.vert: issue with gl_ClipDistance/CullDistance
- baseResults/spv.430.vert: issue gl_ClipDistance
- baseResults/spv.450.tesc: still unknown
- baseResults/spv.dataOut.frag: gl_FragData should not be supported, problem with front end
- baseResults/spv.meshShaderPerViewUserDefined.mesh: seems okay, maybe a problem with SPIRV-Tools
This adds or changes binding/location decorations in 100s of shaders.
It also allows more output (spv.register.autoassign.rangetest.frag)
due to allowing ioMap() to fail.
This was redundant in two ways:
1) it replicated algorithms owned in the front end, and
2) it sometimes left location information on both a block and its members.
Takes some pressure off of issue #304.
Structures don't inherit locations and then explicitly decorate
members with them, so removed this reason to have another instance
of a structure type.
