[trunk r.3708] Any edit to text style set sizeIsSpatiumDependent to true (with patch)

Steps:
1) Create a new score with a title (by deafult title is displayed in 24 pt)
2) Menu "Layout | Page settings...": change Scaling, for instance to 1.364mm
3) Menu "Style | Edit text style..."
4) Change something in the data for style "Title", for instance set it bold, press OK

Result: title is shown not only in bold (as per step 4) ) but also smaller (18.54 pt in the example above) because spatium has been decreased in step 2). Saving the score in .mscx shows that the Title style has become spatium-dependent.

This is the consequence of a missing statement in function void TextStyleDialog::saveStyle(int n) (file textstyle.cpp).

Expected result: Title keeps its status of non-spatium-dependent and keeps its size, regardless of spatium setting.

Patch: the attached diff file inserts the missing statement.

Thanks,

M.