Revert the prune_flags changes.
Revert the prune_flags changes.

The changes break flags such as -framework X -framework Y.

hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR,hlange/LogSoCR