Revert "third_party/protobuf: Update to HEAD (f52e188fe4)"

third_party/protobuf/cmake/examples.cmake

-if(protobuf_VERBOSE)
-  message(STATUS "Protocol Buffers Examples Configuring...")
-endif()
-
-get_filename_component(examples_dir "../examples" ABSOLUTE)
-
-if(protobuf_VERBOSE)
-  message(STATUS "Protocol Buffers Examples Configuring done")
-endif()
-include(ExternalProject)
-
-# Internal utility function: Create a custom target representing a build of examples with custom options.
-function(add_examples_build NAME)
-
-  ExternalProject_Add(${NAME}
-    PREFIX ${NAME}
-    SOURCE_DIR "${examples_dir}"
-    BINARY_DIR ${NAME}
-    STAMP_DIR ${NAME}/logs
-    INSTALL_COMMAND "" #Skip
-    LOG_CONFIGURE 1
-    CMAKE_CACHE_ARGS "-DCMAKE_BUILD_TYPE:STRING=${CMAKE_BUILD_TYPE}"
-                     "-Dprotobuf_VERBOSE:BOOL=${protobuf_VERBOSE}"
-                     ${ARGN}
-  )
-  set_property(TARGET ${NAME} PROPERTY FOLDER "Examples")
-  set_property(TARGET ${NAME} PROPERTY EXCLUDE_FROM_ALL TRUE)
-endfunction()
-
-# Add examples as an external project.
-# sub_directory cannot be used because the find_package(protobuf) call would cause failures with redefined targets.
-add_examples_build(examples "-Dprotobuf_DIR:PATH=${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_CMAKEDIR}")
-add_dependencies(examples libprotobuf protoc)
-
-option(protobuf_BUILD_EXAMPLES_MULTITEST "Build Examples in multiple configurations. Useful for testing." OFF)
-mark_as_advanced(protobuf_BUILD_EXAMPLES_MULTITEST)
-if(protobuf_BUILD_EXAMPLES_MULTITEST)
-  set_property(GLOBAL PROPERTY USE_FOLDERS ON)
-
-  #Build using the legacy compatibility module.
-  add_examples_build(examples-legacy
-    "-Dprotobuf_DIR:PATH=${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_CMAKEDIR}"
-    "-Dprotobuf_MODULE_COMPATIBLE:BOOL=TRUE"
-  )
-  add_dependencies(examples-legacy libprotobuf protoc)
-
-  #Build using the installed library.
-  add_examples_build(examples-installed
-    "-Dprotobuf_DIR:PATH=${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_CMAKEDIR}"
-  )
-
-  #Build using the installed library in legacy compatibility mode.
-  add_examples_build(examples-installed-legacy
-    "-Dprotobuf_DIR:PATH=${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_CMAKEDIR}"
-    "-Dprotobuf_MODULE_COMPATIBLE:BOOL=TRUE"
-  )
-endif()