Part 1 of a series of fixes meant to improve reliability and increase ease of bug fixing for data formatter issues.
We are introducing a new Logger class on the Python side. This has the same purpose, but is unrelated, to the C++ logging facility
The Pythonic logging can be enabled by using the following scripting commands:
(lldb) script Logger._lldb_formatters_debug_level = {0,1,2,...}
0 = no logging
1 = do log
2 = flush after logging each line - slower but safer
3 or more = each time a Logger is constructed, log the function that has created it
more log levels may be added, each one being more log-active than the previous
by default, the log output will come out on your screen, to direct it to a file:
(lldb) script Logger._lldb_formatters_debug_filename = 'filename'
that will make the output go to the file - set to None to disable the file output and get screen logging back
Logging has been enabled for the C++ STL formatters and for Cocoa class NSData - more logging will follow


synthetic children providers for classes list and map (both libstdcpp and libcxx) now have internal capping for safety reasons
this will fix crashers where a malformed list or map would not ever meet our termination conditions

to set the cap to a different value:

(lldb) script {gnu_libstdcpp|libcxx}.{map|list}_capping_size = new_cap (by default, it is 255)

you can optionally disable the loop detection algorithm for lists

(lldb) script {gnu_libstdcpp|libcxx}.list_uses_loop_detector = False

llvm-svn: 153676