LibGUI+LibDraw: Add "Palette" concept for scoped color theming

GApplication now has a palette. This palette contains all the system
theme colors by default, and is inherited by a new top-level GWidget.
New child widgets inherit their parents palette.

It is possible to override the GApplication palette, and the palette
of any GWidget.

The Palette object contains a bunch of colors, each corresponding to
a ColorRole. Each role has a convenience getter as well.

Each GWidget now has a background_role() and foreground_role(), which
are then looked up in their current palette when painting. This means
that you no longer alter the background color of a widget by setting
it directly, rather you alter either its background role, or the
widget's palette.

1 files changed, 2 insertions, 1 deletions

diff --git a/Applications/FontEditor/GlyphMapWidget.cpp b/Applications/FontEditor/GlyphMapWidget.cpp
index e8b88ae62d..1e65cf8d77 100644
--- a/Applications/FontEditor/GlyphMapWidget.cpp
+++ b/Applications/FontEditor/GlyphMapWidget.cpp
@@ -1,4 +1,5 @@
 #include "GlyphMapWidget.h"
+#include <LibDraw/Palette.h>
 #include <LibGUI/GPainter.h>
 
 GlyphMapWidget::GlyphMapWidget(Font& mutable_font, GWidget* parent)
@@ -74,7 +75,7 @@ void GlyphMapWidget::paint_event(GPaintEvent& event)
                 font().max_glyph_width(),
                 font().glyph_height());
             if (glyph == m_selected_glyph) {
-                painter.fill_rect(outer_rect, SystemColor::Selection);
+                painter.fill_rect(outer_rect, palette().selection());
                 painter.draw_glyph(inner_rect.location(), glyph, Color::White);
             } else {
                 painter.draw_glyph(inner_rect.location(), glyph, Color::Black);