GL: Separate dirty bits leading to glUniformBlockBinding The GL backend is special in that it needs to make actual calls (native glUniformBlockBinding) in response to (application) glUniformBlockBinding calls. The other backends just remap the bindings based on that information when creating descriptor sets. Previously, an optimization to track which bindings have changed used the same dirty bits that were used to signify when the GL backend needs to make these native calls. That ended up as a source of bugs. In a previous change [1], the context DIRTY_BIT_UNIFORM_BUFFER_BINDINGS is set when these mappings change, which fixes some of these issues. That change obviates the need for an actual backend sync of programs, except for GL programs that need to make these native calls. This change splits the dirty bits maintained for the purposes of the GL backend, moves them to that backend and removes the program backend sync. [1]: https://chromium-review.googlesource.com/c/angle/angle/+/5228599 Bug: angleproject:8493 Bug: b/318806125 Change-Id: I73c6514e88a116f1cd701cb06da0d8c38f07f7f6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5230137 Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Charlie Lao <cclao@google.com> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>