Export of internal Abseil changes.

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441d1aa02483cdc510eb2fef012b31384fd8e3a6 by Eric Fiselier <ericwf@google.com>:

Fix str_format with non-POSIX libc implementations.

PiperOrigin-RevId: 218441122

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da6190130e74222af6eb161a5593364341370370 by Jon Cohen <cohenjon@google.com>:

Refactor ExceptionSafetyTester::Test in order to remove the levels of indirection related to unpacking tuples.

PiperOrigin-RevId: 218403355
GitOrigin-RevId: 441d1aa02483cdc510eb2fef012b31384fd8e3a6
Change-Id: I6f6b978eb96fe261e8ee41ecdce185e5356a601d

absl/base/exception_safety_testing_test.cc

@@ -770,6 +770,18 @@ TEST(ExceptionCheckTest, ModifyingChecker) {
                   .Test(invoker));
 }
 
+TEST(ExceptionSafetyTesterTest, ResetsCountdown) {
+  auto test =
+      testing::MakeExceptionSafetyTester()
+          .WithInitialValue(ThrowingValue<>())
+          .WithContracts([](ThrowingValue<>*) { return AssertionSuccess(); })
+          .WithOperation([](ThrowingValue<>*) {});
+  ASSERT_TRUE(test.Test());
+  // If the countdown isn't reset because there were no exceptions thrown, then
+  // this will fail with a termination from an unhandled exception
+  EXPECT_TRUE(test.Test());
+}
+
 struct NonCopyable : public NonNegative {
   NonCopyable(const NonCopyable&) = delete;
   NonCopyable() : NonNegative{0} {}