LibGUI: Remove Widget's unused m_{foreground,background}_color

...as well as the few remaining references to set_foreground_color().

These properties are not being used for rendering anymore, presumably
because they completely mess up theming - assigning random white and
gray backgrounds just doesn't work with dark themes.
I've chosen to not replace most of the few remaining uses of this
broken functionality with custom palette colors (the closest
replacement is background_role) for now (except for Minesweeper where
squares with mines are painted red again now), as no one has actually
complained about them being broken, so it must look somewhat decent
(some just look right anyway). :^)

Examples of this are the taskbar buttons, which apparently had a
DarkGray foreground color for minimized windows once - this has since
been replaced with bold/regular font. Another one is the Profiler's
ProfileTimelineWidget, which is supposed to have a white background -
which it didn't have for quite some time, it's grey now (with the
default theme, that is). Doesn't look bad either.

7 files changed, 5 insertions, 19 deletions

diff --git a/Demos/DynamicObject/main.cpp b/Demos/DynamicObject/main.cpp
index dac2bb9617..541aa6ea0d 100644
--- a/Demos/DynamicObject/main.cpp
+++ b/Demos/DynamicObject/main.cpp
@@ -59,7 +59,6 @@ int main([[maybe_unused]] int argc, [[maybe_unused]] char** argv, [[maybe_unused
 
     auto& main_widget = window->set_main_widget<GUI::Widget>();
     main_widget.set_fill_with_background_color(true);
-    main_widget.set_background_color(Color::White);
     auto& layout = main_widget.set_layout<GUI::VerticalBoxLayout>();
     layout.set_margins({ 4, 4, 4, 4 });
 
diff --git a/Demos/HelloWorld/main.cpp b/Demos/HelloWorld/main.cpp
index 0413c0bedd..4c39b30b66 100644
--- a/Demos/HelloWorld/main.cpp
+++ b/Demos/HelloWorld/main.cpp
@@ -59,7 +59,6 @@ int main(int argc, char** argv)
 
     auto& main_widget = window->set_main_widget<GUI::Widget>();
     main_widget.set_fill_with_background_color(true);
-    main_widget.set_background_color(Color::White);
     auto& layout = main_widget.set_layout<GUI::VerticalBoxLayout>();
     layout.set_margins({ 4, 4, 4, 4 });
 
diff --git a/DevTools/HackStudio/FormEditorWidget.cpp b/DevTools/HackStudio/FormEditorWidget.cpp
index efc0d494ec..9e9773d2c7 100644
--- a/DevTools/HackStudio/FormEditorWidget.cpp
+++ b/DevTools/HackStudio/FormEditorWidget.cpp
@@ -36,7 +36,6 @@ FormEditorWidget::FormEditorWidget()
     : m_tool(make<CursorTool>(*this))
 {
     set_fill_with_background_color(true);
-    set_background_color(Color::MidGray);
 
     m_form_widget = add<FormWidget>();
     m_widget_tree_model = WidgetTreeModel::create(*m_form_widget);
diff --git a/DevTools/Profiler/ProfileTimelineWidget.cpp b/DevTools/Profiler/ProfileTimelineWidget.cpp
index bbaf38973f..7d4552d300 100644
--- a/DevTools/Profiler/ProfileTimelineWidget.cpp
+++ b/DevTools/Profiler/ProfileTimelineWidget.cpp
@@ -31,7 +31,6 @@
 ProfileTimelineWidget::ProfileTimelineWidget(Profile& profile)
     : m_profile(profile)
 {
-    set_background_color(Color::White);
     set_fill_with_background_color(true);
     set_fixed_height(80);
 }
diff --git a/Games/Minesweeper/Field.cpp b/Games/Minesweeper/Field.cpp
index bfe1bddd4a..75183d1963 100644
--- a/Games/Minesweeper/Field.cpp
+++ b/Games/Minesweeper/Field.cpp
@@ -252,7 +252,11 @@ void Field::reset()
             square.is_swept = false;
             if (!square.label) {
                 square.label = add<SquareLabel>(square);
-                square.label->set_background_color(Color::from_rgb(0xff4040));
+                // Square with mine will be filled with background color later, i.e. red
+                auto palette = square.label->palette();
+                palette.set_color(Gfx::ColorRole::Base, Color::from_rgb(0xff4040));
+                square.label->set_palette(palette);
+                square.label->set_background_role(Gfx::ColorRole::Base);
             }
             square.label->set_fill_with_background_color(false);
             square.label->set_relative_rect(rect);
diff --git a/Libraries/LibGUI/Widget.h b/Libraries/LibGUI/Widget.h
index 5735d7326f..cde61ef20e 100644
--- a/Libraries/LibGUI/Widget.h
+++ b/Libraries/LibGUI/Widget.h
@@ -214,12 +214,6 @@ public:
     Gfx::ColorRole foreground_role() const { return m_foreground_role; }
     void set_foreground_role(Gfx::ColorRole);
 
-    Color background_color() const { return m_background_color; }
-    Color foreground_color() const { return m_foreground_color; }
-
-    void set_background_color(Color color) { m_background_color = color; }
-    void set_foreground_color(Color color) { m_foreground_color = color; }
-
     void set_autofill(bool b) { set_fill_with_background_color(b); }
 
     Window* window()
@@ -359,8 +353,6 @@ private:
     Gfx::IntRect m_relative_rect;
     Gfx::ColorRole m_background_role;
     Gfx::ColorRole m_foreground_role;
-    Color m_background_color;
-    Color m_foreground_color;
     NonnullRefPtr<Gfx::Font> m_font;
     String m_tooltip;
 
diff --git a/Services/Taskbar/TaskbarWindow.cpp b/Services/Taskbar/TaskbarWindow.cpp
index 9ad590c495..a68dedc4c9 100644
--- a/Services/Taskbar/TaskbarWindow.cpp
+++ b/Services/Taskbar/TaskbarWindow.cpp
@@ -206,12 +206,6 @@ void TaskbarWindow::update_window_button(::Window& window, bool show_as_active)
     auto* button = window.button();
     if (!button)
         return;
-
-    if (window.is_minimized()) {
-        button->set_foreground_color(Color::DarkGray);
-    } else {
-        button->set_foreground_color(Color::Black);
-    }
     button->set_text(window.title());
     button->set_checked(show_as_active);
 }