Change googletest minimum cmake version to 2.8.12, as lower versions are deprecated.

3rdParty/googletest/CMakeLists.txt

 # Note: CMake support is community-based. The maintainers do not use CMake
 # internally.
 
-cmake_minimum_required(VERSION 2.8.8)
+cmake_minimum_required(VERSION 2.8.12)
 
 if (POLICY CMP0048)
   cmake_policy(SET CMP0048 NEW)

3rdParty/googletest/googlemock/CMakeLists.txt

@@ -42,7 +42,7 @@ else()
   cmake_policy(SET CMP0048 NEW)
   project(gmock VERSION ${GOOGLETEST_VERSION} LANGUAGES CXX C)
 endif()
-cmake_minimum_required(VERSION 2.6.4)
+cmake_minimum_required(VERSION 2.8.12)
 
 if (COMMAND set_up_hermetic_build)
   set_up_hermetic_build()

3rdParty/googletest/googletest/CMakeLists.txt

@@ -53,7 +53,7 @@ else()
   cmake_policy(SET CMP0048 NEW)
   project(gtest VERSION ${GOOGLETEST_VERSION} LANGUAGES CXX C)
 endif()
-cmake_minimum_required(VERSION 2.6.4)
+cmake_minimum_required(VERSION 2.8.12)
 
 if (POLICY CMP0063) # Visibility
   cmake_policy(SET CMP0063 NEW)