Revert 100384 - Fix bug in SimulateAttrib0 that did not check for out of memory.

      It also did not correctly check for math overflow. Also fixed
similar bugs in SimulateFixedAttribs

TEST=unit tests
BUG=95625

R=apatrick@chromium.org


Review URL: http://codereview.chromium.org/7845017

TBR=gman@chromium.org
Review URL: http://codereview.chromium.org/7857037

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@100411 0039d316-1c4b-4281-b951-d872f2087c98