Merged r14079 into trunk branch.

Make Isolate::GetHeapStatistics robust against half-initialized isolates.

BUG=2591

R=danno@chromium.org

Review URL: https://codereview.chromium.org/12798010

git-svn-id: https://v8.googlecode.com/svn/trunk@14080 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Rollback of r14079 in trunk branch.

Make Isolate::GetHeapStatistics robust against half-initialized isolates.

BUG=2591

TBR=danno@chromium.org

Review URL: https://codereview.chromium.org/12945012

git-svn-id: https://v8.googlecode.com/svn/trunk@14082 ce2b1a6d-e550-0410-aec6-3dcde31c8c00