Set coalescing ON for Linux Tests target.

DefineOptions.cmake

@@ -22,6 +22,7 @@ endif (P2012)
 if (LINUXTEST)
   set(HAVE_LOCKS OFF)
   set(WITH_EXAMPLES ON)
+  set(WITH_COALESCING ON)
   set(WITH_SHARED_LIB ON)
   set(WITH_DOC ON)
 endif (LINUXTEST)