Fit Algorithm crashes if constraints are applied

[mantid-builder]

Original Reporter: Gesner Passos

This ticket is blocked by :

• TRAC2389

There are some issues related to the Fit Dialog when trying to execute Fit Algorithm from the Algorithms Dock.

• If you add a Tabulated Function composed with a FlatBackground it will not wait you to write the whole Workspace inside the TabulatedFunction, but when you type the first letter, it will write a warning message: "Workspace r not found" if you just typed 'r'. The only possible workaround is to do a Ctrl-V of the workspace name.
• If you try to add a constraint for the Scaling factor of the TabulatedFunction, for example, to say that the LowerBound is 0.001. It will crash the MantidPlot with the following message:
  • Segmentation fault (core dumped)

[mantid-builder]

This issue was originally trac ticket 6000