Reland "Harden NumberToSize against overflows."

The callers to NumberToSize are supposed to validate the number, but
this adds a last line of defense.

TBR=jkummerow@chromium.org, ulan@chromium.org

Review URL: https://codereview.chromium.org/61733021

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17737 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Runtime CHECK for overflow in NewTypedArray.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/62713006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17739 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Avoid integer overflow in CopyMap.

R=jkummerow@chromium.org

Review URL: https://chromiumcodereview.appspot.com/63173023

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17740 ce2b1a6d-e550-0410-aec6-3dcde31c8c00