Fix darwin run-test problems

Bug: 17428908

(cherry picked from commit 8a4064e2c0987637b11afcc656478d3113d81618)

Change-Id: Ica403bef3e7d93bf6e9197c44b77e39683e04d55
diff --git a/test/run-test b/test/run-test
index eed28a5..b140fbf 100755
--- a/test/run-test
+++ b/test/run-test
@@ -223,10 +223,10 @@
 #
 # Cannot use realpath, as it does not exist on Mac.
 # Cannot us a simple "cd", as the path might not be created yet.
-# Use -m option of readlink: canonicalizes, but allows non-existing components.
+# Cannot use readlink -m, as it does not exist on Mac.
+# Fallback to nuclear option:
 noncanonical_tmp_dir=$tmp_dir
-tmp_dir="`cd $oldwd ; readlink -m $tmp_dir`"
-
+tmp_dir="`cd $oldwd ; python -c "import os; print os.path.realpath('$tmp_dir')"`"
 mkdir -p $tmp_dir
 
 if [ "$basic_verify" = "true" ]; then