tdf#163620 [API CHANGE] Add UI for libreoffice themes

Instead of Color, we have Light and  Dark in the registry. So each theme extension
will specify  dark and  light color  values for  each "customizable  element" like
DocColor etc. Under appearance we have three radio buttons - light/dark/system. If
system  is selected  then light/dark  colors are  switched based  on the  system's
theme.  if  explicitly light/dark  is  selected  - that  color  is  used from  the
registry.

ColorConfigValue now has three entries  nColor, nLightColor, nDarkColor. nColor is
used as a cache for the color being used at the moment. This is to avoid otherwise
expensive  function calls  + hundreds  of modifications  in the  codebase just  to
change nColor. nColor  is cached either when  the theme is loaded  or when changes
are committed in `ColorConfig_Impl::ImplCommit()`.

Now, if  Automatic theme is selected  then themes is disabled  and the application
uses the system  colors. If some other scheme is  selected like "CustomTheme" etc,
then LibreOffice themes/UI color customization is enabled and the theme colors are
used.

Instead of a scroll window, now we have  a combobox for the registry entries and a
single  color dropdown  to select  the  color value.  This color  dropdown is  for
convinience in case the user wants  to change some specific color that's bothering
him. For themeing, theme extensions should be used.

API CHANGE
+ remove Color in favour of Light and Dark
+ AppBackground has additional two - BackgroundType and Bitmap
+ remove officecfg::Office::Common::Misc::Appearnce in favor of
officecfg::Office::Common::Appearance::ApplicationAppearance
+ move LibreofficeTheme under officecfg::Office::Common::Appearance

UI
+ it looks like https://i.imgur.com/UMxjfuC.png which is a little
different from how the [mockup] on the ticket describes it, and that's
because of lack of time due to upcomming feature freeze.

+ system/light/dark allow the user to switch between light/dark modes
based on either the system theme (system) or by manually specifying
light/dark.

+ ui themeing and color customization is disabled when automatic theme
is selected, and enabled otherwise.

[mockup]: https://bug-attachments.documentfoundation.org/attachment.cgi?id=197469

Change-Id: I1a7f70dfe44b81f863814f87e8d46e146c0e3d5a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/174835
Reviewed-by: Heiko Tietze <heiko.tietze@documentfoundation.org>
Tested-by: Jenkins
Reviewed-by: Sahil Gautam <sahil.gautam.extern@allotropia.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/desktop/qa/desktop_lib/test_desktop_lib.cxx b/desktop/qa/desktop_lib/test_desktop_lib.cxx
index 11db3d75398b..7bca2926e948 100644
--- a/desktop/qa/desktop_lib/test_desktop_lib.cxx
+++ b/desktop/qa/desktop_lib/test_desktop_lib.cxx
@@ -2270,7 +2270,9 @@ void DesktopLOKTest::testPaintPartTileDifferentSchemes()
         svtools::EditableColorConfig aColorConfig;
         svtools::ColorConfigValue aValue;
         aValue.bIsVisible = true;
-        aValue.nColor = aDarkColor;
+        // aValue.nColor is just used for cache. please see Change: I1a7f70dfe44b81f863814f87e8d46e146c0e3d5a
+        aValue.nLightColor = aDarkColor;
+        aValue.nDarkColor = aDarkColor;
         aColorConfig.SetColorValue(svtools::DOCCOLOR, aValue);
         aColorConfig.AddScheme(u"Dark"_ustr);
     }
@@ -2280,7 +2282,8 @@ void DesktopLOKTest::testPaintPartTileDifferentSchemes()
         svtools::EditableColorConfig aColorConfig;
         svtools::ColorConfigValue aValue;
         aValue.bIsVisible = true;
-        aValue.nColor = COL_WHITE;
+        aValue.nLightColor = COL_WHITE;
+        aValue.nDarkColor = COL_WHITE;
         aColorConfig.SetColorValue(svtools::DOCCOLOR, aValue);
         aColorConfig.AddScheme(u"Light"_ustr);
     }