Use CMakePackageConfigHelpers to generate version file

The version file that already existed looks like it was generated
by this module. Replace it with proper usage of the module.

cmake/gRPCConfigVersion.cmake.in

@@ -1,11 +0,0 @@
-set(PACKAGE_VERSION "@PACKAGE_VERSION@")
-
-# Check whether the requested PACKAGE_FIND_VERSION is compatible
-if("${PACKAGE_VERSION}" VERSION_LESS "${PACKAGE_FIND_VERSION}")
-    set(PACKAGE_VERSION_COMPATIBLE FALSE)
-else()
-    set(PACKAGE_VERSION_COMPATIBLE TRUE)
-    if ("${PACKAGE_VERSION}" VERSION_EQUAL "${PACKAGE_FIND_VERSION}")
-        set(PACKAGE_VERSION_EXACT TRUE)
-    endif()
-endif()

templates/CMakeLists.txt.template

@@ -614,13 +614,18 @@
     )
   endif()
 
-  foreach(_config gRPCConfig gRPCConfigVersion)
+  include(CMakePackageConfigHelpers)
-    configure_file(cmake/<%text>${_config}</%text>.cmake.in
+
-      <%text>${_config}</%text>.cmake @ONLY)
+  configure_file(cmake/gRPCConfig.cmake.in
-    install(FILES <%text>${CMAKE_CURRENT_BINARY_DIR}/${_config}</%text>.cmake
+    gRPCConfig.cmake @ONLY)
-      DESTINATION <%text>${gRPC_INSTALL_CMAKEDIR}</%text>
+  write_basic_package_version_file(<%text>${CMAKE_CURRENT_BINARY_DIR}/</%text>gRPCConfigVersion.cmake
-    )
+    VERSION <%text>${PACKAGE_VERSION}</%text>
-  endforeach()
+    COMPATIBILITY AnyNewerVersion)
+  install(FILES
+      <%text>${CMAKE_CURRENT_BINARY_DIR}/</%text>gRPCConfig.cmake
+      <%text>${CMAKE_CURRENT_BINARY_DIR}/</%text>gRPCConfigVersion.cmake
+    DESTINATION <%text>${gRPC_INSTALL_CMAKEDIR}</%text>
+  )
 
   install(FILES <%text>${CMAKE_CURRENT_SOURCE_DIR}/etc/roots.pem</%text>
     DESTINATION <%text>${gRPC_INSTALL_SHAREDIR}</%text>)