Export of internal Abseil changes

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66a0a46462692378f77518f9db766a218bfac40b by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 300565981

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2a1ad67662b2e22beec7d3be019e6bba23c41c7f by Derek Mauro <dmauro@google.com>:

Fix CompressedTuple move constructor on MSVC
Imports GitHub #637

PiperOrigin-RevId: 300545840

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a3ee3ad036bbb6b0031121fd58299e5c59a243e1 by Derek Mauro <dmauro@google.com>:

Disable LLVM's XRay instrumentation on Android
Fixes #626

PiperOrigin-RevId: 300540906

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87999244b1f825e585ec12a431086cb60daeb24f by Gennadiy Rozental <rogeeff@google.com>:

Increase max cord depth by 2.
After reviewing of the paper we can prove that the algorithm in fact can lead to slightly larger max depth.

PiperOrigin-RevId: 300422376

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98de175ee8ad33290ef883c167c2de4414a11007 by Abseil Team <absl-team@google.com>:

Use *opt/opt-> instead of opt.value() in an example, after checking the optional has a value.

PiperOrigin-RevId: 300253502

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1107aa0acf0fe743ef50173e02e48f0d4eb572ef by Derek Mauro <dmauro@google.com>:

Stop overriding the default system C++ dialect in CMake

CMake on MacOS has some very strange defaults, like Wno-c++11-extensions,
and doesn't seem to respect CMAKE_CXX_STANDARD, so use CMAKE_CXX_FLAGS instead.

PiperOrigin-RevId: 300180753
GitOrigin-RevId: 66a0a46462692378f77518f9db766a218bfac40b
Change-Id: Icd7b84c49306441b012cb87f244cc92a11697db8

ci/macos_xcode_cmake.sh

@@ -36,7 +36,7 @@ for compilation_mode in ${ABSL_CMAKE_BUILD_TYPES}; do
   time cmake ${ABSEIL_ROOT} \
     -GXcode \
     -DCMAKE_BUILD_TYPE=${compilation_mode} \
-    -DCMAKE_CXX_STANDARD=11 \
+    -DCMAKE_CXX_FLAGS=-std=c++14 \
     -DABSL_USE_GOOGLETEST_HEAD=ON \
     -DABSL_RUN_TESTS=ON
   time cmake --build .