Add Isolate parameter to HandleScope::NumberOfHandles.

LOG=y
BUG=324225
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/128233002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18510 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Prepare push to trunk.  Now working on version 3.24.14.

R=rossberg@chromium.org
TBR=rossberg@chromium.org

Review URL: https://codereview.chromium.org/131413002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18511 ce2b1a6d-e550-0410-aec6-3dcde31c8c00