Translator: Generate Ops for all built-in functions EOpCallBuiltInFunction is removed in this change, as well as the "op": "auto" property in builtin_function_declarations.txt. Instead, gen_builtin_symbols.py automatically generates Ops for every built-in function and generates the TOperator enum accordingly. This simplifies SPIR-V code generation by allowing switches to be used on operators instead of string comparisons. Bug: angleproject:4589 Bug: angleproject:4889 Change-Id: Ia351524400b0e12a10a5572e27e9b88c6ec2e61c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2958869 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jonah Ryan-Davis <jonahr@google.com> Reviewed-by: Tim Van Patten <timvp@google.com>