It takes way too long to finish tag parsing of modified files after a find/replace

[sean-mcmanus]

1. Do a find/replace over many files.
2. View the C/C++ logging for "tag parsing" messages.

Bug: It takes way too long to tag parse. Like each tag parse takes 1-2 seconds on Linux (seemed like 0.5-1 seconds on Windows), which is a lot slower than the speed of the initial tag parsing when a database is first created. From initial debugging it seemed like it could be some database update/lock issue.

But I don't think we've gotten a user complaint about this so I'm not sure how important it is to make this scenario faster.