This reverts commit r20169, it heavily regresses a Mozilla test:

make -j32 arm64.release.check TESTFLAGS=--time TESTJOBS=mozilla/js1_5/Regress/regress-280769-2

Before:
--- Total time: 00:01.928 ---
   1 (00:01.911) mozilla/js1_5/Regress/regress-280769-2
   2 (00:01.910) mozilla/js1_5/Regress/regress-280769-2
   3 (00:01.910) mozilla/js1_5/Regress/regress-280769-2

After:
--- Total time: 01:36.025 ---
   1 (01:36.004) mozilla/js1_5/Regress/regress-280769-2
   2 (01:35.403) mozilla/js1_5/Regress/regress-280769-2
   3 (01:32.098) mozilla/js1_5/Regress/regress-280769-2

TBR=ulan@chromium.org

Review URL: https://codereview.chromium.org/209333004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20187 ce2b1a6d-e550-0410-aec6-3dcde31c8c00