Revert parts of r223594. Use DYLD_LIBRARY_PATH on OSX when running tests.

llvm-svn: 223598

libcxx/test/lit.cfg

@@ -234,6 +234,7 @@ class Configuration(object):
         self.configure_obj_root()
         self.configure_use_system_lib()
         self.configure_use_clang_verify()
+        self.configure_env()
         self.configure_std_flag()
         self.configure_compile_flags()
         self.configure_link_flags()
@@ -558,7 +559,9 @@ class Configuration(object):
             self.lit_config.note(
                 "inferred target_triple as: %r" % self.config.target_triple)
 
-
+    def configure_env(self):
+        if sys.platform == 'darwin' and not self.use_system_lib:
+            self.env['DYLD_LIBRARY_PATH'] = os.path.join(self.obj_root, 'lib')
 
 # name: The name of this test suite.
 config.name = 'libc++'