Remove EOpInternalFunctionCall It's cleaner to mark internal functions by using the TName class, similarly to TIntermSymbol. TEST=angle_unittests BUG=angleproject:1116 Change-Id: I12a03a3dea42b3fc571fa25a1b11d0161f24de72 Reviewed-on: https://chromium-review.googlesource.com/291621 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Olli Etuaho <oetuaho@nvidia.com>