Add pkg-config file declaring Abseil dependency

See protocolbuffers/protobuf#12439 for more information

PiperOrigin-RevId: 525796488

Author: mkruskal-google

CMakeLists.txt

@@ -73,6 +73,11 @@ if (utf8_range_ENABLE_INSTALL)
   install(FILES "${PROJECT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
     DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
   )
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/utf8_range.pc.cmake
+                 ${CMAKE_CURRENT_BINARY_DIR}/utf8_range.pc @ONLY)
+  install(
+    FILES ${CMAKE_CURRENT_BINARY_DIR}/utf8_range.pc
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
 
   # Install public headers explicitly.
   install(FILES utf8_range.h utf8_validity.h

cmake/utf_range.pc.cmake

@@ -0,0 +1,12 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=@CMAKE_INSTALL_PREFIX@
+libdir=@CMAKE_INSTALL_FULL_LIBDIR@
+includedir=@CMAKE_INSTALL_FULL_INCLUDEDIR@
+
+Name: UTF8 Range
+Description: Google's Data Interchange Format
+Version: 1.0
+Requires: absl_strings
+Libs: -L${libdir} -lprotobuf-lite @CMAKE_THREAD_LIBS_INIT@
+Cflags: -I${includedir}
+Conflicts: protobuf