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diff --git a/node_modules/fbjs/lib/getScrollPosition.js b/node_modules/fbjs/lib/getScrollPosition.js
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+++ b/node_modules/fbjs/lib/getScrollPosition.js
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+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @typechecks
+ */
+
+'use strict';
+
+var getDocumentScrollElement = require('./getDocumentScrollElement');
+var getUnboundedScrollPosition = require('./getUnboundedScrollPosition');
+
+/**
+ * Gets the scroll position of the supplied element or window.
+ *
+ * The return values are bounded. This means that if the scroll position is
+ * negative or exceeds the element boundaries (which is possible using inertial
+ * scrolling), you will get zero or the maximum scroll position, respectively.
+ *
+ * If you need the unbound scroll position, use `getUnboundedScrollPosition`.
+ *
+ * @param {DOMWindow|DOMElement} scrollable
+ * @return {object} Map with `x` and `y` keys.
+ */
+function getScrollPosition(scrollable) {
+  var documentScrollElement = getDocumentScrollElement(scrollable.ownerDocument || scrollable.document);
+  if (scrollable.Window && scrollable instanceof scrollable.Window) {
+    scrollable = documentScrollElement;
+  }
+  var scrollPosition = getUnboundedScrollPosition(scrollable);
+
+  var viewport = scrollable === documentScrollElement ? scrollable.ownerDocument.documentElement : scrollable;
+
+  var xMax = scrollable.scrollWidth - viewport.clientWidth;
+  var yMax = scrollable.scrollHeight - viewport.clientHeight;
+
+  scrollPosition.x = Math.max(0, Math.min(scrollPosition.x, xMax));
+  scrollPosition.y = Math.max(0, Math.min(scrollPosition.y, yMax));
+
+  return scrollPosition;
+}
+
+module.exports = getScrollPosition;
+\ No newline at end of file