Export of internal Abseil changes

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972333fe1e43427849b8a634aa35061e81be3642 by Abseil Team <absl-team@google.com>:

Replace deprecated thread annotations macros.

PiperOrigin-RevId: 267332619

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7039c6dc499a31c372b4872eda0772455931c360 by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 267220271

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a3f524d2afc2535686f206a7ce06961016349d7a by Abseil Team <absl-team@google.com>:

Factor kernel_timeout out of synchronization.

PiperOrigin-RevId: 267217304

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90287de4114ef9a06cafe50256a2d03349772c21 by Abseil Team <absl-team@google.com>:

Fixed comment typo.

PiperOrigin-RevId: 267198532

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d312c1a1e52aeca1871ff0deead416d09a7f237e by Gennadiy Rozental <rogeeff@google.com>:

Internal change

PiperOrigin-RevId: 267185804
GitOrigin-RevId: 972333fe1e43427849b8a634aa35061e81be3642
Change-Id: Ia8a2f877c57cef9854aad48f1753af872fc04dc8
diff --git a/absl/flags/parse.cc b/absl/flags/parse.cc
index e9dd420..16c4d68 100644
--- a/absl/flags/parse.cc
+++ b/absl/flags/parse.cc
@@ -44,11 +44,11 @@
 ABSL_CONST_INIT absl::Mutex processing_checks_guard(absl::kConstInit);
 
 ABSL_CONST_INIT bool flagfile_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 ABSL_CONST_INIT bool fromenv_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 ABSL_CONST_INIT bool tryfromenv_needs_processing
-    GUARDED_BY(processing_checks_guard) = false;
+    ABSL_GUARDED_BY(processing_checks_guard) = false;
 
 }  // namespace
 }  // namespace flags_internal