Export of internal Abseil changes

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330051e00cd57ee516b4eaf656965656ffbcd0bc by Abseil Team <absl-team@google.com>:

Fix indentation in comment.

PiperOrigin-RevId: 287997504

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35fb1a893e708031ba4fc0db460875eb0d31820e by Abseil Team <absl-team@google.com>:

Enable compile-time enforcement that absl::Substitute patterns to not contain unescaped $ symbols.

absl::Substitute already considers unescaped $ symbols undefined behavior and crashes when it's passed them in debug builds.  Some code isn't ever built in debug mode, though, and inadvertently used some unescaped $ symbols, which led to surprising results.  This change will prevent that problem from happening in the future.
PiperOrigin-RevId: 287906643

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c5762833ebde6d7110bf68041a823b571c238e9e by Gennadiy Rozental <rogeeff@google.com>:

Move all the flag data into a single place instead of being split between handle and flag object.

After this change CommandLineFlag will not hold any data anymore. And we also do not need to pass the CommandLineFlag around in Abseil Flag implementation to report flag name and location.

PiperOrigin-RevId: 287899076

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8b5fb644f1e3d9267b7a75106fe9a72c886db786 by Derek Mauro <dmauro@google.com>:

Upgrade CI testing to Bazel 2.0.0 and Clang 407ac2eb5f13

-fno-sanitize-blacklist is to workaround
https://github.com/bazelbuild/bazel/issues/10510

PiperOrigin-RevId: 287875363

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a20cc1d58895de2babc3748a6c79d1d6813734ef by Abseil Team <absl-team@google.com>:

Make ABSL_RETIRED_FLAG behave consistently with ABSL_FLAG.

Before the change:
ABSL_RETIRED_FLAG does not compile when there are competing ctors in the type, even when ABSL_FLAG does.

After the change:
ABSL_RETIRED_FLAG compiles when ABSL_FLAG does.

PiperOrigin-RevId: 286483183

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1cff7e67329d2be9e50bee1f2e76ef9ffd2edde5 by Abseil Team <absl-team@google.com>:

Support C++20 erase_if API in unordered associative containers

See [unord.set.erasure]: https://eel.is/c++draft/unord.set.erasure
See [unord.map.erasure]: https://eel.is/c++draft/unord.map.erasure

PiperOrigin-RevId: 286461140
GitOrigin-RevId: 330051e00cd57ee516b4eaf656965656ffbcd0bc
Change-Id: I5513110b41c2af08a44da54612cff341ac5c6607

7 files changed, 9 insertions, 7 deletions

diff --git a/ci/cmake_install_test.sh b/ci/cmake_install_test.sh
index 6a3c19bd..e85474c2 100755
--- a/ci/cmake_install_test.sh
+++ b/ci/cmake_install_test.sh
@@ -28,5 +28,5 @@ time docker run \
     --rm \
     -e CFLAGS="-Werror" \
     -e CXXFLAGS="-Werror" \
-    gcr.io/google.com/absl-177019/linux_gcc-latest:20191018 \
+    gcr.io/google.com/absl-177019/linux_gcc-latest:20200102 \
     /bin/bash CMake/install_test_project/test.sh $@
diff --git a/ci/linux_clang-latest_libcxx_asan_bazel.sh b/ci/linux_clang-latest_libcxx_asan_bazel.sh
index fa38ff20..24efe3b7 100755
--- a/ci/linux_clang-latest_libcxx_asan_bazel.sh
+++ b/ci/linux_clang-latest_libcxx_asan_bazel.sh
@@ -36,7 +36,7 @@ if [ -z ${EXCEPTIONS_MODE:-} ]; then
   EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
 fi
 
-readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20191018"
+readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20200102"
 
 # USE_BAZEL_CACHE=1 only works on Kokoro.
 # Without access to the credentials this won't work.
@@ -76,6 +76,7 @@ for std in ${STD}; do
           --copt="-fsanitize=float-divide-by-zero" \
           --copt="-fsanitize=nullability" \
           --copt="-fsanitize=undefined" \
+          --copt="-fno-sanitize-blacklist" \
           --copt=-Werror \
           --keep_going \
           --linkopt="-fsanitize=address" \
diff --git a/ci/linux_clang-latest_libcxx_bazel.sh b/ci/linux_clang-latest_libcxx_bazel.sh
index c3319a1b..40a27c0b 100755
--- a/ci/linux_clang-latest_libcxx_bazel.sh
+++ b/ci/linux_clang-latest_libcxx_bazel.sh
@@ -36,7 +36,7 @@ if [ -z ${EXCEPTIONS_MODE:-} ]; then
   EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
 fi
 
-readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20191018"
+readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20200102"
 
 # USE_BAZEL_CACHE=1 only works on Kokoro.
 # Without access to the credentials this won't work.
diff --git a/ci/linux_clang-latest_libcxx_tsan_bazel.sh b/ci/linux_clang-latest_libcxx_tsan_bazel.sh
index 200541b9..00257b36 100755
--- a/ci/linux_clang-latest_libcxx_tsan_bazel.sh
+++ b/ci/linux_clang-latest_libcxx_tsan_bazel.sh
@@ -36,7 +36,7 @@ if [ -z ${EXCEPTIONS_MODE:-} ]; then
   EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
 fi
 
-readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20191018"
+readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20200102"
 
 # USE_BAZEL_CACHE=1 only works on Kokoro.
 # Without access to the credentials this won't work.
@@ -73,6 +73,7 @@ for std in ${STD}; do
           --copt="-DDYNAMIC_ANNOTATIONS_ENABLED=1" \
           --copt="-DTHREAD_SANITIZER" \
           --copt="-fsanitize=thread" \
+          --copt="-fno-sanitize-blacklist" \
           --copt=-Werror \
           --keep_going \
           --linkopt="-fsanitize=thread" \
diff --git a/ci/linux_clang-latest_libstdcxx_bazel.sh b/ci/linux_clang-latest_libstdcxx_bazel.sh
index 5ea18373..9fe71d37 100755
--- a/ci/linux_clang-latest_libstdcxx_bazel.sh
+++ b/ci/linux_clang-latest_libstdcxx_bazel.sh
@@ -36,7 +36,7 @@ if [ -z ${EXCEPTIONS_MODE:-} ]; then
   EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
 fi
 
-readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20191018"
+readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_clang-latest:20200102"
 
 # USE_BAZEL_CACHE=1 only works on Kokoro.
 # Without access to the credentials this won't work.
diff --git a/ci/linux_gcc-latest_libstdcxx_bazel.sh b/ci/linux_gcc-latest_libstdcxx_bazel.sh
index a6efa197..70d24d79 100755
--- a/ci/linux_gcc-latest_libstdcxx_bazel.sh
+++ b/ci/linux_gcc-latest_libstdcxx_bazel.sh
@@ -36,7 +36,7 @@ if [ -z ${EXCEPTIONS_MODE:-} ]; then
   EXCEPTIONS_MODE="-fno-exceptions -fexceptions"
 fi
 
-readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_gcc-latest:20191018"
+readonly DOCKER_CONTAINER="gcr.io/google.com/absl-177019/linux_gcc-latest:20200102"
 
 # USE_BAZEL_CACHE=1 only works on Kokoro.
 # Without access to the credentials this won't work.
diff --git a/ci/linux_gcc-latest_libstdcxx_cmake.sh b/ci/linux_gcc-latest_libstdcxx_cmake.sh
index ec328748..7effa0c0 100755
--- a/ci/linux_gcc-latest_libstdcxx_cmake.sh
+++ b/ci/linux_gcc-latest_libstdcxx_cmake.sh
@@ -47,7 +47,7 @@ for std in ${ABSL_CMAKE_CXX_STANDARDS}; do
       --rm \
       -e CFLAGS="-Werror" \
       -e CXXFLAGS="-Werror" \
-      gcr.io/google.com/absl-177019/linux_gcc-latest:20191018 \
+      gcr.io/google.com/absl-177019/linux_gcc-latest:20200102 \
       /bin/bash -c "
         cd /buildfs && \
         cmake /abseil-cpp \