First step in refactoring the logging system to allow the logging messages to have other destinations than an open file.

This change introduces a log message builder which builds the log message in a static string buffer instead of formatting the log message through fprintf. Currently this message can only be written to a file afterwards.

Changed the code related events to use the log message builder.
Review URL: http://codereview.chromium.org/20406

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1284 ce2b1a6d-e550-0410-aec6-3dcde31c8c00