[Gimp-gui] scaling layers hangs GIMP if a typo is made

[SardonicIconoclast <SardonicIconoclast protonmail com>]

This happens almost every day to me.  Its been this way since the beginning, I think.

I tried to type '200' into the dialog box just now, for instance- to try to get a 200% scale on one axi,. and due to desired logic of keeping the existing values there. .actually I somehow got 102000 on one axis.  SO it tries to allocate too much video memory (or something) and I lose all my unsaved work.

Maybe we could get thos dimensions to scale no larger than some X % at a time?  Or warn the user before creating a giant texture?   Like the current behavior for 

perspective transformation. I think.

In general great work though.  Thanks!

Sent with ProtonMail secure email.