Re-land "Add hover state border to overview task item"

Fix: 249859410
Test: b/291266459
Change-Id: I5ac1e9e77439e587f11c994d22fdc72d20d8502d

quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchTaskView.java

@@ -80,7 +80,7 @@ public class KeyboardQuickSwitchTaskView extends ConstraintLayout {
         setWillNotDraw(false);
 
         mBorderColor = ta.getColor(
-                R.styleable.TaskView_borderColor, DEFAULT_BORDER_COLOR);
+                R.styleable.TaskView_focusBorderColor, DEFAULT_BORDER_COLOR);
         ta.recycle();
     }