AGODIA,
There is no legal requirement for manufacturers to flight test aircraft in contaminated conditions, therefore they don’t!
They normally present data titled “For Information Only” which is based on parameters established by NASA in the 1960’s using a Convair 880. The FAA has tried to regulate Contaminated runway operations. Their latest missive is AC91-6A but as the name suggests this document is over 10 years old, during which time the aviation industry has failed to consolidate the information into the FARS, but you are expected to use this information to make a correct decision every time you takeoff…………
Unfortunately if something goes wrong it will be you sitting in the court of law and not the airline industry for failing you…..
Good Luck.
Mutt.