Export of internal Abseil changes.

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da04b8cd21f6225d71397471474d34a77df0efd6 by Jon Cohen <cohenjon@google.com>:

Don't use std::any, std::optional, std::variant, and friends on MacOS versions older than 10.14.

Although Xcode 10 includes those headers and makes the types available to use, according to https://developer.apple.com/documentation/xcode_release_notes/xcode_10_release_notes, on MacOS 10.13 and earlier use of any functions (std::get, for example) results in an error message to upgrade to MacOS 10.14.

This fixes https://github.com/abseil/abseil-cpp/issues/207.  See that issue for more information on the error generated.

PiperOrigin-RevId: 221844618

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1d99f77b4c60c5b0d7984f46e8ed63a3f969c635 by Jon Cohen <cohenjon@google.com>:

raw_hash_set_test is still flaky under gcc 4.8.  Since we now have the probe_test, we don't need the PerfectRatio tests.  Just remove them.

PiperOrigin-RevId: 221843042

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135cbb2a5d90963256518b3b59fe6710815e5dfa by Abseil Team <absl-team@google.com>:

Update absl/algorithm/CMakeLists.txt to use new functions
i.e. absl_cc_(library|test)

PiperOrigin-RevId: 221828348

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1a5abde4f17f998ae89d87155d59f982a70202d8 by Jon Cohen <cohenjon@google.com>:

Internal change

PiperOrigin-RevId: 221708245

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e03e031d4de39275989f695c768b0940cce1ff16 by Matt Armstrong <marmstrong@google.com>:

Log to FATAL in throw_delegate.h

ABSL_RAW_LOG(FATAL, ...) is guaranteed to abort.
Previously, the code was logging to ERROR and
calling abort() explicitly, which defeated any
integration with absl::raw_logging_internal::AbortHook().

These changes are limited to Abseil internal APIs.

PiperOrigin-RevId: 221696513

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d13691523a3f9a5367fd1194cf9604bf4a969029 by Shahriar Rouf <nafi@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 221694877

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f4044c56d44ba0ac2a9f218ed55f1b1f9e985eae by Abseil Team <absl-team@google.com>:

Update absl/base/CMakeLists.txt to use new functions
i.e. absl_cc_(library|test)

PiperOrigin-RevId: 221676669
GitOrigin-RevId: da04b8cd21f6225d71397471474d34a77df0efd6
Change-Id: If6621e10d096a39b6a056a072c2727a0df0b0620