[clang] [analyzer][Solver] Early return if sym is concrete on assuming (PR #115579)

[Balazs Benics via cfe-commits]

steakhal wrote:

> > @danix800 Could you please have a look at the failed test, such that we could reapply this PR? I reverted this soon after I realized the broken test is from this PR.
> 
> The test randomly fails for unknown reason, on VS2019~2022, after [1c154bd](https://github.com/llvm/llvm-project/commit/1c154bd755153b5c6ada4bbed58facf23f6abffc) (seems totally irrelevant to this randomness). Not sure if it's a compiler bug.

I'm not sure I see why. The logs I linked in the revert only showed a single test failure. The new test we added in this PR. This suggests close correlations. Maybe the content of the "constraints" map in the State is dumped in a non-deterministic order? And we just happened to step on it now.

https://github.com/llvm/llvm-project/pull/115579