Export of internal Abseil changes

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51798d2ac9c95ee8955955c5d8d78b4c9592ecf7 by Derek Mauro <dmauro@google.com>:

Correctly install pkgconfig files under CMAKE_INSTALL_LIBDIR
Fixes #931

PiperOrigin-RevId: 366816645

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fbaad678b54dae70e4cd9f4442b4fef9efb71b30 by Abseil Team <absl-team@google.com>:

Add a kDefaultStatusToStringMode representing the default StatusToStringMode.

PiperOrigin-RevId: 366478305

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25b4be6a591e8b25338a00be1273cd6cae6b0165 by Evan Brown <ezb@google.com>:

Fix a typo in a comment.

PiperOrigin-RevId: 366464483

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6add48ed8f633c219f02c6ef8af876f8dbaa9955 by Abseil Team <absl-team@google.com>:

Update comment to mention absl::container_literal::Layout which is what is used instead of gtl::Layout.

PiperOrigin-RevId: 366452345
GitOrigin-RevId: 51798d2ac9c95ee8955955c5d8d78b4c9592ecf7
Change-Id: I8e68bc55d81445b2f6f707943fed9075cd402844

CMake/AbseilHelpers.cmake

@@ -181,7 +181,7 @@ Requires:${PC_DEPS}\n\
 Libs: -L\${libdir} $<JOIN:${ABSL_CC_LIB_LINKOPTS}, > $<$<NOT:$<BOOL:${ABSL_CC_LIB_IS_INTERFACE}>>:-labsl_${_NAME}>\n\
 Cflags: -I\${includedir}${PC_CFLAGS}\n")
       INSTALL(FILES "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc"
-              DESTINATION "${CMAKE_INSTALL_PREFIX}/lib/pkgconfig")
+              DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
     endif()
   endif()
 

absl/container/internal/btree.h

@@ -484,8 +484,8 @@ class btree_node {
                        std::is_same<std::greater<key_type>,
                                     key_compare>::value)>;
 
-  // This class is organized by gtl::Layout as if it had the following
-  // structure:
+  // This class is organized by absl::container_internal::Layout as if it had
+  // the following structure:
   //   // A pointer to the node's parent.
   //   btree_node *parent;
   //

absl/status/status.h

@@ -293,6 +293,8 @@ enum class StatusToStringMode : int {
   kWithPayload = 1 << 0,
   // ToString will include all the extra data this Status has.
   kWithEverything = ~kWithNoExtraData,
+  // Default mode used by ToString. Its exact value might change in the future.
+  kDefault = kWithPayload,
 };
 
 // absl::StatusToStringMode is specified as a bitmask type, which means the
@@ -509,7 +511,7 @@ class Status final {
   // result, and the payloads to be printed use the status payload printer
   // mechanism (which is internal).
   std::string ToString(
-      StatusToStringMode mode = StatusToStringMode::kWithPayload) const;
+      StatusToStringMode mode = StatusToStringMode::kDefault) const;
 
   // Status::IgnoreError()
   //