Add a util method of creating Icon with Drawable

- Add a util method to help create Icon with Drawable so that
users don't need to handle bitmaps
- Add support for creating with ColorDrawable

Test: robotest
Fixes: 124407373
Change-Id: I1897256821cc804a5e599d967feb84a3bcd689a9

src/com/android/settings/homepage/contextualcards/slices/NotificationChannelSlice.java

@@ -30,9 +30,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
-import android.graphics.Bitmap;
-import android.graphics.Canvas;
-import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Bundle;
@@ -243,7 +240,7 @@ public class NotificationChannelSlice implements CustomSliceable {
             return null;
         }
 
-        return IconCompat.createWithBitmap(Utils.drawableToBitmap(drawable));
+        return Utils.createIconWithDrawable(drawable);
     }
 
     @VisibleForTesting