Return "DIDNOTHING" from preallocate.
Return "DIDNOTHING" from preallocate.

Before, it always returned SUCCESS.  Now it returns success iff it did
something.  If it does nothing it returns DIDNOTHING.

UIKit0/HyperDex,pombredanne/HyperDex,UIKit0/HyperDex,hyc/HyperDex,UIKit0/HyperDex,pombredanne/HyperDex,jtk54/HyperDex,jtk54/HyperDex,vashstorm/HyperDex,cactorium/HyperDex,cactorium/HyperDex,cactorium/HyperDex,hyc/HyperDex,rescrv/HyperDex,cactorium/HyperDex,jtk54/HyperDex,hyc/HyperDex,cactorium/HyperDex,jtk54/HyperDex,pombredanne/HyperDex,UIKit0/HyperDex,UIKit0/HyperDex,UIKit0/HyperDex,rescrv/HyperDex,hyc/HyperDex,hyc/HyperDex,cactorium/HyperDex,pombredanne/HyperDex,jtk54/HyperDex,vashstorm/HyperDex,tempbottle/HyperDex,jtk54/HyperDex,tempbottle/HyperDex,cactorium/HyperDex,rescrv/HyperDex,rescrv/HyperDex,vashstorm/HyperDex,rescrv/HyperDex,rescrv/HyperDex,jtk54/HyperDex,jtk54/HyperDex,tempbottle/HyperDex,tempbottle/HyperDex,pombredanne/HyperDex,tempbottle/HyperDex,vashstorm/HyperDex,cactorium/HyperDex,rescrv/HyperDex,tempbottle/HyperDex,vashstorm/HyperDex,cactorium/HyperDex,jtk54/HyperDex,rescrv/HyperDex,hyc/HyperDex,hyc/HyperDex,hyc/HyperDex,pombredanne/HyperDex,tempbottle/HyperDex,UIKit0/HyperDex,pombredanne/HyperDex,pombredanne/HyperDex,UIKit0/HyperDex,pombredanne/HyperDex,tempbottle/HyperDex,UIKit0/HyperDex,tempbottle/HyperDex,vashstorm/HyperDex,vashstorm/HyperDex,vashstorm/HyperDex,rescrv/HyperDex,vashstorm/HyperDex