Avoid pre-aging when debugger is active

BUG=None
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/47023003

Patch from Ross McIlroy <rmcilroy@chromium.org>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17443 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[Sheriff] Mark flaky test.

BUG=v8:2921
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/54423002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17444 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
[Sheriff] Mark failing test for nacl port.

BUG=v8:2978
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/50333005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17445 ce2b1a6d-e550-0410-aec6-3dcde31c8c00