Fix compare functions used by std::sort
In commit 3306cb3e (Nov 22, 2016), the obsolete qSort function was replaced by std::sort. However, there is a subtile difference: qSort was able to cope with non-strict weak ordering given back by the compare function, whereas std::sort is not, possibly resulting in out-of-bound accesses and crashes. In a previous commit 2856bba6, a compare function in treemap.cpp was fixed, but we missed fixing a few other compare functions which now are used by std::sort. This fixes bug 385127.
Showing with 24 additions and 8 deletions