CMake: Install TESTONLY libraries and their dependencies (#1442)

This patch cherry-picks 807763a7

#1407 

---------

Co-authored-by: Derek Mauro <dmauro@google.com>

CMake/AbseilHelpers.cmake

@@ -153,7 +153,6 @@ function(absl_cc_library)
 
   # Generate a pkg-config file for every library:
   if(ABSL_ENABLE_INSTALL)
-    if(NOT ABSL_CC_LIB_TESTONLY)
     if(absl_VERSION)
       set(PC_VERSION "${absl_VERSION}")
     else()
@@ -217,7 +216,6 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
     INSTALL(FILES "${CMAKE_BINARY_DIR}/lib/pkgconfig/absl_${_NAME}.pc"
             DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
   endif()
-  endif()
 
   if(NOT ABSL_CC_LIB_IS_INTERFACE)
     if(_build_type STREQUAL "dll_dep")
@@ -346,9 +344,7 @@ Cflags: -I\${includedir}${PC_CFLAGS}\n")
     endif()
   endif()
 
-  # TODO currently we don't install googletest alongside abseil sources, so
-  # installed abseil can't be tested.
-  if(NOT ABSL_CC_LIB_TESTONLY AND ABSL_ENABLE_INSTALL)
+  if(ABSL_ENABLE_INSTALL)
     install(TARGETS ${_NAME} EXPORT ${PROJECT_NAME}Targets
           RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
           LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}

absl/base/config.h

@@ -112,7 +112,7 @@
 // LTS releases can be obtained from
 // https://github.com/abseil/abseil-cpp/releases.
 #define ABSL_LTS_RELEASE_VERSION 20230125
-#define ABSL_LTS_RELEASE_PATCH_LEVEL 2
+#define ABSL_LTS_RELEASE_PATCH_LEVEL 3
 
 // Helper macro to convert a CPP variable to a string literal.
 #define ABSL_INTERNAL_DO_TOKEN_STR(x) #x