Merge pull request #7812 from IgniteUI/mpopov/fix-item-line-subtitle-contrast

fix item subtitle contrast color

Author: simeonoff

projects/igniteui-angular/src/lib/core/styles/themes/schemas/light/_list.scss

@@ -190,9 +190,9 @@ $_bootstrap-list: extend(
 /// @property {Map} item-text-color-hover [igx-color: ('grays', 900)] - The list item text color.
 /// @property {Map} item-text-color-active [igx-color: ('grays', 900)] - The active list item text color.
 ///
-/// @property {Color} item-subtitle-color [igx-color: ('grays', 600)] - The list item subtitle color.
-/// @property {Color} item-subtitle-color-hover [igx-color: ('grays', 600)] - The list item subtitle hover color.
-/// @property {Color} item-subtitle-color-active [igx-color: ('grays', 600)] - The list item subtitle active color.
+/// @property {Color} item-subtitle-color [igx-color: ('grays', 800)] - The list item subtitle color.
+/// @property {Color} item-subtitle-color-hover [igx-color: ('grays', 800)] - The list item subtitle hover color.
+/// @property {Color} item-subtitle-color-active [igx-color: ('grays', 800)] - The list item subtitle active color.
 ///
 /// @property {Color} item-action-color [igx-color: ('grays', 600)] - The list item action color.
 /// @property {Color} item-action-color-hover [igx-color: ('grays', 600)] - The list item action hover color.
@@ -257,15 +257,15 @@ $_indigo-list: extend(
         ),
 
         item-subtitle-color: (
-            igx-color: ('grays', 600)
+            igx-color: ('grays', 800)
         ),
 
         item-subtitle-color-hover: (
-            igx-color: ('grays', 600)
+            igx-color: ('grays', 800)
         ),
 
         item-subtitle-color-active: (
-            igx-color: ('grays', 600)
+            igx-color: ('grays', 800)
         ),
 
         item-thumbnail-color: (