Moving SKHighlightOverlay

Summary: Moving FlipperKitLayoutPlugin/FlipperKitPluginUtils/SKHighlightOverlay to shared folder, so Layout and WorkingRange plugins can depend on it

Reviewed By: kevin0571

Differential Revision: D17156396

fbshipit-source-id: 3f17371f2ab4818924d61e6cfb243f60ad1f2892

iOS/Plugins/FlipperKitPluginUtils/FlipperKitHighlightOverlay/SKHighlightOverlay.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the LICENSE
+ * file in the root directory of this source tree.
+ */
+#import <UIKit/UIKit.h>
+
+@interface SKHighlightOverlay : NSObject
+
++ (instancetype)sharedInstance;
++ (UIColor*)overlayColor;
+
+- (void)mountInView:(UIView *)view withFrame:(CGRect)frame;
+- (void)unmount;
+
+@end