Move stuff out of vendor/react_contrib/

Summary: This was a confusing place for them. BoundingDimensions, Position, and Touchable were only used in Touchable; StaticContainer I moved to Libraries/Components.

@​public

Reviewed By: @vjeux

Differential Revision: D2530730

fb-gh-sync-id: e636a6b7259c2bd3ab52c82ebd59a6c66c9e7e7a

Libraries/Components/Touchable/BoundingDimensions.js

@@ -0,0 +1,37 @@
+/**
+ * @providesModule BoundingDimensions
+ */
+
+"use strict";
+
+var PooledClass = require('PooledClass');
+
+var twoArgumentPooler = PooledClass.twoArgumentPooler;
+
+/**
+ * PooledClass representing the bounding rectangle of a region.
+ *
+ * @param {number} width Width of bounding rectangle.
+ * @param {number} height Height of bounding rectangle.
+ * @constructor BoundingDimensions
+ */
+function BoundingDimensions(width, height) {
+  this.width = width;
+  this.height = height;
+}
+
+/**
+ * @param {HTMLElement} element Element to return `BoundingDimensions` for.
+ * @return {BoundingDimensions} Bounding dimensions of `element`.
+ */
+BoundingDimensions.getPooledFromElement = function(element) {
+  return BoundingDimensions.getPooled(
+    element.offsetWidth,
+    element.offsetHeight
+  );
+};
+
+PooledClass.addPoolingTo(BoundingDimensions, twoArgumentPooler);
+
+module.exports = BoundingDimensions;
+