Memory leak when searching. Only tested on Qt Creator 2.5.0 but it may be on the later versions as the changelogs don't mention anything.

Steps to reproduce:
1. Search file system/directory with a lot of files for common strings or even just 1 character.
2. Watch memory usage go up. This is ok since there are a lot of matches to keep track of.
3. Clear the search results (doing a new search does nothing as it keeps the old search matches in history)

Expected result: memory usage should go down

Actual result: 5 GB memory leak