C++11 left-overs

[h-vetinari]

Following #1127 & 97ab3dc, there's still ~60 files mentioning of C++11 in the code base.

Of note is IMO

abseil-cpp/absl/base/options.h

Lines 105 to 106 in 34838ef

	// A value of 0 means to use Abseil's implementation. This requires only C++11
	// support, and is expected to work on every toolchain we support.

because that's where the ABI-relevant options get set, and it implies that abseil would still compile to the C++11 ABI, which I'm pretty sure is not the case anymore.

[h-vetinari]

there's still ~60 files mentioning of C++11 in the code base.

This has not really been changed by #2117 (CC @DrishtiTripathi2230); there's still a lot of these files around. Stuff like // NOLINT(build/c++11) hardly makes sense anymore if c++11 isn't supported anymore.

IMO this issue should be reopened.

[DrishtiTripathi2230]

Thanks for the follow-up , #2117 fixed the two comments from the original issue, but I see the rest is still open. I'd like to take this on and will follow up with a PR covering the remaining C++11 mentions and the NOLINT(build/c++11) markers.

[derekmauro]

Please do not remove the NOLINT(build/c++11) markers. We would have to update the linter first. We don't have time for that at the moment.

[DrishtiTripathi2230]

Went through the remaining C++11 mentions (skipping NOLINT markers per @derekmauro's note). They're all historical/descriptive — explaining what C++11 added or old compiler quirks in tests, nothing claiming Abseil currently needs C++11. Didn't find anything else to fix beyond options.h. Let me know if I'm missing something.