Reduce delay in keypress (input) in Query Tool

Hi Dave,

It has been noticed that on certain systems, that typing into the Query
Tool is extremely slow and characters get printed very slowly. The probable
reason behind this is on each key press in Query Tool OnChangeStc() gets
called in frmQuery which in turn calls updateMenu(). In updateMenu() we
call the canSaveAsImage(), which internally updates the ModelSize of GQB
with the updateModelSize() function.

Attached is the patch that fixes this issue by disabling the call
to canSaveAsImage() when called updateMenu() is called from OnChangeStc().
In this way the model size of GQB won't get updated on press of each key.

Let me know views/thoughts on the same.

Thanks,

--
regards,

*Dhiraj Chawla*
Software Engineer
EnterpriseDB Corporation
The Enterprise PostgreSQL Company

Phone: +91-20-30589522