Separate blacklist length for different error type.

_From [zhao...@google.com](https://code.google.com/u/106321947286816917100/) on February 25, 2014 15:52:26_

For error reporting, we use blacklist to filter possible false positives and uninterested from system libraries for better error reports, i.e., we report an error as a potential error if the top n (4) frames are all in blacklist.

However, different error may have different length requirements. For example, we can tolerant more system lib frames on the callstack for handle leaks report than the number of framens for uninit error report.

So it would be nice if we can have a per-error blacklist number of frames setting.

_Original issue: http://code.google.com/p/drmemory/issues/detail?id=1454_