Provide a mechanism to do some pre-loading of symbols up front.

Loading a shared library can require a large amount of work; rather than do that serially for each library,
this patch will allow parallelization of the symbols and debug info name indexes.

From scott.smith@purestorage.com

https://reviews.llvm.org/D32598


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@301609 91177308-0d34-0410-b5e6-96231b3b80d8
11 files changed