Export of internal Abseil changes.

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e7f892a0b9b313b434c5f9e9a2365b377204b60e by Abseil Team <absl-team@google.com>:

Remove internal CaseEqual helper now that we have the equivalent absl::EqualsIgnoreCase.

PiperOrigin-RevId: 225189084

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722af2c74766d2fe3cee13c8dc886d39aedda597 by Abseil Team <absl-team@google.com>:

Add -Wno-extra-semi-stmt to silence that warning.

The [-Wno-extra-semi] is already disabled in the build.  This
change will allow the build to remain consistent across newer
versions of clang which are now issuing a new similiar warning
[-Wextra-semi-stmt]:

  https://clang.llvm.org/docs/ReleaseNotes.html#major-new-features
  https://clang.llvm.org/docs/DiagnosticsReference.html#wextra-semi-stmt

PiperOrigin-RevId: 225185101

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f7fd6244b4efcf0331631a54b7b0cf5f1f691a89 by CJ Johnson <johnsoncj@google.com>:

Move using directive in swap implementation

PiperOrigin-RevId: 225017825

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3005841725df5b9cdb35c8a5319bb4c78b5dc2b7 by Abseil Team <absl-team@google.com>:

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

PiperOrigin-RevId: 224860689

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eeaf7099924b182472bfea3636ef6d9a39adfc50 by CJ Johnson <johnsoncj@google.com>:

Prefer public method over private for InlinedVector allocator access

PiperOrigin-RevId: 224825775

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db9d218e3ca7ab400eef97778b720cb082a03281 by Eric Fiselier <ericwf@google.com>:

Take advantage of secret libc++ resize uninitialized function in string.

PiperOrigin-RevId: 224817877
GitOrigin-RevId: e7f892a0b9b313b434c5f9e9a2365b377204b60e
Change-Id: I051beee37ee03f0570bd2e068355ad75c8bdfcf8

absl/copts/copts.py

@@ -58,6 +58,7 @@ COPT_VARS = {
         # Turned off as they include valid C++ code.
         "-Wno-comma",
         "-Wno-extra-semi",
+        "-Wno-extra-semi-stmt",
         "-Wno-packed",
         "-Wno-padded",
         ###