Always initialize the debugger eagerly.

There is no point doing it lazily, since compiling and executing the tiniest piece of code triggers lazy init.
Also removed some dead code.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/265593004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21135 ce2b1a6d-e550-0410-aec6-3dcde31c8c00