Add getBounds to geometry

src/ol/geom/geometry.js

@@ -1,3 +1,4 @@
+goog.require('ol.Extent');
 goog.provide('ol.geom.Coordinate');
 goog.provide('ol.geom.CoordinateArray');
 goog.provide('ol.geom.Geometry');
@@ -10,6 +11,20 @@ goog.provide('ol.geom.Geometry');
 ol.geom.Geometry = function() {};
 
 
+/**
+ * The dimension of this geometry (2 or 3).
+ * @type {number}
+ */
+ol.geom.Geometry.prototype.dimension;
+
+
+/**
+ * Get the rectangular 2D evelope for this geoemtry.
+ * @return {ol.Extent} The bounding rectangular envelope.
+ */
+ol.geom.Geometry.prototype.getBounds = goog.abstractMethod;
+
+
 /**
  * @typedef {Array.<number>}
  */