Remove no-op functionality from IdentifyBuiltIns and refactor Adding array built-ins like gl_FragData and gl_LastFragData to the symbol table with a name that included their size in brackets was incorrect and unnecessary. Remove this. The array built-ins should only be added with their proper name and with an array type. Also refactor the code to reduce unnecessary repetition of conditions. The previous version attempted to split the built-ins that had dependencies on resources into their own part of the code, but this split was not clearly defined and only made the code harder to follow and prone to issues. TEST=WebGL conformance tests Change-Id: I7a77865a594864a22f3b566f9d3da1d0ead46466 Reviewed-on: https://chromium-review.googlesource.com/258751 Reviewed-by: Nicolas Capens <capn@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Olli Etuaho <oetuaho@nvidia.com>