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diff --git a/node_modules/fbjs/lib/Scroll.js.flow b/node_modules/fbjs/lib/Scroll.js.flow
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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.
+ *
+ * @providesModule Scroll
+ */
+
+/**
+ * @param {DOMElement} element
+ * @param {DOMDocument} doc
+ * @return {boolean}
+ */
+function _isViewportScrollElement(element, doc) {
+  return !!doc && (element === doc.documentElement || element === doc.body);
+}
+
+/**
+ * Scroll Module. This class contains 4 simple static functions
+ * to be used to access Element.scrollTop/scrollLeft properties.
+ * To solve the inconsistencies between browsers when either
+ * document.body or document.documentElement is supplied,
+ * below logic will be used to alleviate the issue:
+ *
+ * 1. If 'element' is either 'document.body' or 'document.documentElement,
+ *    get whichever element's 'scroll{Top,Left}' is larger.
+ * 2. If 'element' is either 'document.body' or 'document.documentElement',
+ *    set the 'scroll{Top,Left}' on both elements.
+ */
+
+const Scroll = {
+  /**
+   * @param {DOMElement} element
+   * @return {number}
+   */
+  getTop: function (element) {
+    const doc = element.ownerDocument;
+    return _isViewportScrollElement(element, doc) ?
+    // In practice, they will either both have the same value,
+    // or one will be zero and the other will be the scroll position
+    // of the viewport. So we can use `X || Y` instead of `Math.max(X, Y)`
+    doc.body.scrollTop || doc.documentElement.scrollTop : element.scrollTop;
+  },
+
+  /**
+   * @param {DOMElement} element
+   * @param {number} newTop
+   */
+  setTop: function (element, newTop) {
+    const doc = element.ownerDocument;
+    if (_isViewportScrollElement(element, doc)) {
+      doc.body.scrollTop = doc.documentElement.scrollTop = newTop;
+    } else {
+      element.scrollTop = newTop;
+    }
+  },
+
+  /**
+   * @param {DOMElement} element
+   * @return {number}
+   */
+  getLeft: function (element) {
+    const doc = element.ownerDocument;
+    return _isViewportScrollElement(element, doc) ? doc.body.scrollLeft || doc.documentElement.scrollLeft : element.scrollLeft;
+  },
+
+  /**
+   * @param {DOMElement} element
+   * @param {number} newLeft
+   */
+  setLeft: function (element, newLeft) {
+    const doc = element.ownerDocument;
+    if (_isViewportScrollElement(element, doc)) {
+      doc.body.scrollLeft = doc.documentElement.scrollLeft = newLeft;
+    } else {
+      element.scrollLeft = newLeft;
+    }
+  }
+};
+
+module.exports = Scroll;
+\ No newline at end of file