[gimp] app: maintain common settings when editing Brightness-Contrast/Levels as Levels/Curves

[Ell <ell src gnome org>]

commit 987447f18f5d018c3f679de926670f1d5e9de988
Author: Ell <ell_se yahoo com>
Date:   Tue Apr 14 17:59:32 2020 +0300

    app: maintain common settings when editing Brightness-Contrast/Levels as Levels/Curves
    
    When converting Brightness-Contrast to Levels, and Levels to
    Curves, make sure to copy the common settings as well as the
    operation-specific settings.

 app/operations/gimpbrightnesscontrastconfig.c | 4 ++++
 app/operations/gimplevelsconfig.c             | 4 ++++
 2 files changed, 8 insertions(+)
---
diff --git a/app/operations/gimpbrightnesscontrastconfig.c b/app/operations/gimpbrightnesscontrastconfig.c
index 1564614587..75ee36aa1c 100644
--- a/app/operations/gimpbrightnesscontrastconfig.c
+++ b/app/operations/gimpbrightnesscontrastconfig.c
@@ -181,6 +181,10 @@ gimp_brightness_contrast_config_to_levels_config (GimpBrightnessContrastConfig *
 
   levels = g_object_new (GIMP_TYPE_LEVELS_CONFIG, NULL);
 
+  gimp_operation_settings_config_copy_base (GIMP_CONFIG (config),
+                                            GIMP_CONFIG (levels),
+                                            0);
+
   brightness = config->brightness / 2.0;
   slant = tan ((config->contrast + 1) * G_PI_4);
 
diff --git a/app/operations/gimplevelsconfig.c b/app/operations/gimplevelsconfig.c
index 253f5501ee..87cf1e3d73 100644
--- a/app/operations/gimplevelsconfig.c
+++ b/app/operations/gimplevelsconfig.c
@@ -714,6 +714,10 @@ gimp_levels_config_to_curves_config (GimpLevelsConfig *config)
 
   curves = g_object_new (GIMP_TYPE_CURVES_CONFIG, NULL);
 
+  gimp_operation_settings_config_copy_base (GIMP_CONFIG (config),
+                                            GIMP_CONFIG (curves),
+                                            0);
+
   curves->trc = config->trc;
 
   for (channel = GIMP_HISTOGRAM_VALUE;