scrolledwindow: Remove unused variable
scrolledwindow: Don't use LIGHTEN operator

For the overshoot gradient, using OVER is fine. Simplifies the code and
increases performance.
scrolledwindow: Rewrite overshoot code with regular styling

Instead of drawing a gradient in the background color, draw a CSS box.

And change the theme so instead of setting just a background color it
draws a gradient.

The resulting visuals are the same.
theming: Use gtk_style_context_peek_property()

instead of outdated accessors.
print: Improve sheet drawing a bit

This is only one step in the right direction. Long term this code should
probably be replaced by real widgets.
stylecontext: Deprecate functions

- gtk_style_context_get_background_color()
- gtk_style_context_get_border_color()

Those functions shouldn't be used anymore, because they don't represent
anything from the CSS styling we support. The background color often
isn't used due to background images and there are actually 4 different
border colors (1 for each side) - if there isn't also a border image in
use.
cellrendereraccel: Remove unused variables
fontchooserwidget: Use text attributes for the preview

... instead of adding a custom CSS provider.
stylecontext: Add missing docs for deprecations
gtk-demo: Properly override font color in combobox example
gtk-demo: Remove unneeded code

Overlays are transparent by default, no need to override them to be.
gtk-demo: Improve flowbox demo code

Overriding the background color for a color swatch is wrong. The color
is not the background, it's the foreground, so it should be painted in
a draw signal handler.
gtk-demo: Remove useless code in colorsel example

We have the color stored in a global variable already. There is
absolutely no need to also force it into the CSS machinery.
gtk-demo: Replace old code

"Hey I know, let's do an easter egg!"
"What kind of easter egg?"
"We can nest lots of textviews!"
"Sounds cool!"
...
"But how does one see a textview inside a textview?"
"What do you mean?"
"Well, it just looks like black text on a white background."
"You mean it's the same as if we just duplicated the text?"
"Yeah!"
"Hrm, maybe we can put a frame around it."
"Sounds good. I'll stuff the textviews in a GtkFrame."
"What? Why? Let's use a GtkEventBox and override its background"
"Why is that a good idea when we have GtkFrame?"
"Because I said so!"
"Okay."
widget-factory: Add a sidebar example
widget-factory: Make the record button more interesting
GtkBuilder: Undo the type name heuristic changes

These turned out to break existing ui files, concretely
GWeatherLocationEntry was no longer guessed correctly.

Update the testcases to reflect this, and add a testcase
for GWeather.
GtkBuilder: Don't use deprecated types in examples
imcontextxim: Remove broken custom drawing code

Just use regular GtkWindow styling instead.
libgail: Add deprecation guards