Clean up: remove background colour option from composite bar actions

src/vs/workbench/browser/parts/activitybar/activitybarPart.ts

@@ -207,7 +207,7 @@ export class ActivitybarPart extends Part {
 			badgeBackground: theme.getColor(ACTIVITY_BAR_BADGE_BACKGROUND),
 			badgeForeground: theme.getColor(ACTIVITY_BAR_BADGE_FOREGROUND),
 			dragAndDropBackground: theme.getColor(ACTIVITY_BAR_DRAG_AND_DROP_BACKGROUND),
-			backgroundColor: null, activeBorderBottomColor: null,
+			activeBorderBottomColor: null,
 		};
 	}
 

src/vs/workbench/browser/parts/compositeBarActions.ts

@@ -113,7 +113,6 @@ export class ActivityAction extends Action {
 }
 
 export interface ICompositeBarColors {
-	backgroundColor: Color;
 	activeBorderBottomColor: Color;
 	activeForegroundColor: Color;
 	inactiveForegroundColor: Color;
@@ -157,16 +156,16 @@ export class ActivityActionItem extends BaseActionItem {
 		const theme = this.themeService.getTheme();
 		const colors = this.options.colors(theme);
 
-		if (this.options.icon) {
-			const foreground = this._action.checked ? colors.activeForegroundColor : colors.inactiveForegroundColor;
-			this.label.style.backgroundColor = foreground ? foreground.toString() : null;
-		} else if (this.label) {
-			const background = colors.backgroundColor;
-			const foreground = this._action.checked ? colors.activeForegroundColor : colors.inactiveForegroundColor;
-			const borderBottomColor = this._action.checked ? colors.activeBorderBottomColor : null;
-			this.label.style.backgroundColor = background ? background.toString() : null;
-			this.label.style.color = foreground ? foreground.toString() : null;
-			this.label.style.borderBottomColor = borderBottomColor ? borderBottomColor.toString() : null;
+		if (this.label) {
+			if (this.options.icon) {
+				const foreground = this._action.checked ? colors.activeForegroundColor : colors.inactiveForegroundColor;
+				this.label.style.backgroundColor = foreground ? foreground.toString() : null;
+			} else {
+				const foreground = this._action.checked ? colors.activeForegroundColor : colors.inactiveForegroundColor;
+				const borderBottomColor = this._action.checked ? colors.activeBorderBottomColor : null;
+				this.label.style.color = foreground ? foreground.toString() : null;
+				this.label.style.borderBottomColor = borderBottomColor ? borderBottomColor.toString() : null;
+			}
 		}
 
 		// Badge

src/vs/workbench/browser/parts/panel/panelPart.ts

@@ -95,7 +95,6 @@ export class PanelPart extends CompositePart<Panel> implements IPanelService {
 			compositeSize: 0,
 			overflowActionSize: 44,
 			colors: theme => ({
-				backgroundColor: theme.getColor(PANEL_BACKGROUND),
 				activeBorderBottomColor: theme.getColor(PANEL_ACTIVE_TITLE_BORDER),
 				activeForegroundColor: theme.getColor(PANEL_ACTIVE_TITLE_FOREGROUND),
 				inactiveForegroundColor: theme.getColor(PANEL_INACTIVE_TITLE_FOREGROUND),