Changes imported from Abseil "staging" branch:

- 93fb81f991e9079769aa28381426f318a1c64377 Add an iterable container of valid absl::LogSeverity valu... by Abseil Team <absl-team@google.com>

GitOrigin-RevId: 93fb81f991e9079769aa28381426f318a1c64377
Change-Id: I63d2c6fe6865f5f92a2260368c58585bc994b5e4

absl/base/log_severity.h

@@ -16,6 +16,8 @@
 #ifndef ABSL_BASE_INTERNAL_LOG_SEVERITY_H_
 #define ABSL_BASE_INTERNAL_LOG_SEVERITY_H_
 
+#include <array>
+
 #include "absl/base/attributes.h"
 
 namespace absl {
@@ -27,6 +29,13 @@ enum class LogSeverity : int {
   kFatal = 3,
 };
 
+// Returns an iterable of all standard `absl::LogSeverity` values, ordered from
+// least to most severe.
+constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
+  return {{absl::LogSeverity::kInfo, absl::LogSeverity::kWarning,
+           absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
+}
+
 constexpr const char* LogSeverityName(absl::LogSeverity s) {
   return s == absl::LogSeverity::kInfo
              ? "INFO"