HC: popover checkbox buttons fix

Last bit keeping https://bugzilla.gnome.org/show_bug.cgi?id=734945
open

themes/HighContrast/gtk-3.0/_common.scss

@@ -927,6 +927,7 @@ GtkTreeView.view.progressbar { //Progressbar in treeview cells
   }
   .button.flat,
   .button.flat:hover {
+    color: $fg_color;
     text-shadow: none;
     transition: none;
   }
@@ -1354,16 +1355,6 @@ GtkCheckButton.text-button, GtkRadioButton.text-button {
     &:inconsistent {
       -gtk-icon-source: -gtk-icontheme('#{$a}-mixed-symbolic');
     }
-    &:selected, &:selected:focus {
-      // :selected:focus not to get overridden by .view style
-      color: transparentize($selected_fg_color,0.9);
-      &:active {
-        color: $selected_fg_color;
-        &:backdrop {
-          color: $backdrop_base_color;
-        }
-      }
-    }
     &:backdrop {
       color: transparentize($backdrop_fg_color,0.9);
       &:selected { color: transparentize($backdrop_base_color,0.9); }

themes/HighContrast/gtk-3.0/gtk.css

@@ -991,6 +991,7 @@ GtkTreeView.view.progressbar {
     border: 0; }
   .popover .button.flat,
   .popover .button.flat:hover {
+    color: #000;
     text-shadow: none;
     transition: none; }
   .popover.osd {
@@ -1423,12 +1424,6 @@ GtkCheckButton.text-button, GtkRadioButton.text-button {
       color: transparent; }
   .check:inconsistent {
     -gtk-icon-source: -gtk-icontheme("checkbox-mixed-symbolic"); }
-  .check:selected, .check:selected:focus {
-    color: rgba(255, 255, 255, 0.1); }
-    .check:selected:active, .check:selected:focus:active {
-      color: #fff; }
-      .check:selected:active:backdrop, .check:selected:focus:active:backdrop {
-        color: #fff; }
   .check:backdrop {
     color: rgba(0, 0, 0, 0.1); }
     .check:backdrop:selected {
@@ -1457,12 +1452,6 @@ GtkCheckButton.text-button, GtkRadioButton.text-button {
       color: transparent; }
   .radio:inconsistent {
     -gtk-icon-source: -gtk-icontheme("radio-mixed-symbolic"); }
-  .radio:selected, .radio:selected:focus {
-    color: rgba(255, 255, 255, 0.1); }
-    .radio:selected:active, .radio:selected:focus:active {
-      color: #fff; }
-      .radio:selected:active:backdrop, .radio:selected:focus:active:backdrop {
-        color: #fff; }
   .radio:backdrop {
     color: rgba(0, 0, 0, 0.1); }
     .radio:backdrop:selected {