Eclipse: improve (fix ?) version detection on OSX

This is probably related to a framework installation I guess.
This is part of the patch in #13367 from Nicholas Yue.

Alex

Modules/CMakeFindEclipseCDT4.cmake

@@ -24,6 +24,9 @@ FUNCTION(_FIND_ECLIPSE_VERSION)
     GET_FILENAME_COMPONENT(_REALPATH_CMAKE_ECLIPSE_EXECUTABLE "${CMAKE_ECLIPSE_EXECUTABLE}" REALPATH)
     GET_FILENAME_COMPONENT(_ECLIPSE_DIR "${_REALPATH_CMAKE_ECLIPSE_EXECUTABLE}" PATH)
     FILE(GLOB _ECLIPSE_FEATURE_DIR "${_ECLIPSE_DIR}/features/org.eclipse.platform*")
+    IF(APPLE AND NOT _ECLIPSE_FEATURE_DIR)
+      FILE(GLOB _ECLIPSE_FEATURE_DIR "${_ECLIPSE_DIR}/../../../features/org.eclipse.platform*")
+    ENDIF()
     IF("${_ECLIPSE_FEATURE_DIR}" MATCHES ".+org.eclipse.platform_([0-9]+\\.[0-9]+).+")
       SET(_ECLIPSE_VERSION ${CMAKE_MATCH_1})
     ENDIF()