Revert "Fix SOURCE_DIR in HandleGTest.cmake (#703)" (#704)

cmake/HandleGTest.cmake

@@ -75,10 +75,12 @@ macro(build_external_gtest)
   endforeach()
 endmacro(build_external_gtest)
 
-macro(build_gtest_from_dir)
+if (BENCHMARK_ENABLE_GTEST_TESTS)
+  if (IS_DIRECTORY ${CMAKE_SOURCE_DIR}/googletest)
+    set(GTEST_ROOT "${CMAKE_SOURCE_DIR}/googletest")
     set(INSTALL_GTEST OFF CACHE INTERNAL "")
     set(INSTALL_GMOCK OFF CACHE INTERNAL "")
-  add_subdirectory(${GTEST_ROOT} build)
+    add_subdirectory(${CMAKE_SOURCE_DIR}/googletest)
     set(GTEST_BOTH_LIBRARIES gtest gmock gmock_main)
     foreach(HEADER test mock)
       # CMake 2.8 and older don't respect INTERFACE_INCLUDE_DIRECTORIES, so we
@@ -94,15 +96,6 @@ macro(build_gtest_from_dir)
       endif()
       list(APPEND GTEST_INCLUDE_DIRS ${HEADER_PATH_${HEADER}})
     endforeach()
-endmacro()
-
-if (BENCHMARK_ENABLE_GTEST_TESTS)
-  if (IS_DIRECTORY ${CMAKE_SOURCE_DIR}/googletest)
-    set(GTEST_ROOT "${CMAKE_SOURCE_DIR}/googletest")
-    build_gtest_from_dir()
-  elseif (IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/googletest)
-    set(GTEST_ROOT "${CMAKE_CURRENT_SOURCE_DIR}/googletest")
-    build_gtest_from_dir()
   elseif(BENCHMARK_DOWNLOAD_DEPENDENCIES)
     build_external_gtest()
   else()