Eliminate Program::mLinkResolved boolean Since mLinkResolved boolean is always kept in sync with the presence of mLinkingState structure, we can remove the former and replace access with checks for the latter being nullptr. Bug: angleproject:4644 Change-Id: Ib385b5c3881946d762ad48e6534c84d15e50f673 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2209319 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Tim Van Patten <timvp@google.com> Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>