* InsetBox and GuiBox: Use proper empty length instead of the broken -9.99col% trick
* some slight changes to the logic of GuiBox to make sure that values are set as needed.
* lengthToWidget(): handle properly the empty length case. All the other related Qt helpers did it already, it was probably an oversight. Also set the default_unit parameter as optional (not needed in this patch actually, but I got carried away :)
* allow generating LaTeX code for an empty length, since some broken code does that.
If there is a new toolbar, it will not be restored by Qt and we need to
initialize it ourselves. However, it is not so easy to find out which
toolbars are restored by Qt and which are not. For this, the setVisible
function of GuiToolbar is 'misused'. If the visibility is set, the toolbar
must have been restored by Qt and we should leave it alone.
LyX uses QTemporaryFile to create a unique temporary directory. This
temporary directory will consist of two random characters and the process
identifier (PID).
Currently, the two random characters are often the same because Qt's
random generator was not seeded. If there are a lot of lyx temporary
directories accumulated, the chance of failing to find a unique temporary
directory is (N/100)%.
The temporary directories can be left behind if either LyX crashes, or
when a file in the temporary directory is opened in another viewer when
LyX closes. This can be a pdf that is viewed in a reader that disallows
the file to be removed while viewing it.
InsetInfos of the type ICON have a graphics Inset in their paragraph.
These insets were inserted without a font. This lead to an assertion in
Paragraph::fontSpan because the fontlist_ of the paragraph is empty.
Move the cursor in front of a bibitem and press enter.
Paragraph::fixBiblio will insert a new bibitem without a font in the new
paragraph. This will make Paragraph::fontSpan assert because the fontlist_
of the new paragraph is empty.
Using "Font no_font" in case no font was supplied was wrong. Instantiating a font object without specifying the language lead to a font object having the default_language that is hardcoded to "english". See Language::read().
This caused that there were spurious language changes in the LaTeX output
and made some document uncompilable.
This reverts commit 3619954590.
