Complete revert.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@598 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/Grid.js

@@ -63,27 +63,25 @@ OpenLayers.Layer.Grid.prototype = Object.extend( new OpenLayers.Layer(), {
             }
             return;
         }
-        var gridBounds = this.getGridBounds();
         if (!this.grid || zoomChanged) {
             this._initTiles();
-        } else {
+        } else { 
             var i = 0;
-            while (gridBounds.bottom > bounds.bottom) {
+            while (this.getGridBounds().bottom > bounds.bottom) {
                this.insertRow(false); 
             }
-            while (gridBounds.left > bounds.left) {
+            while (this.getGridBounds().left > bounds.left) {
                this.insertColumn(true); 
             }
-            while (gridBounds.top < bounds.top) {
+            while (this.getGridBounds().top < bounds.top) {
                this.insertRow(true); 
             }
-            while (gridBounds.right < bounds.right) {
+            while (this.getGridBounds().right < bounds.right) {
                this.insertColumn(false); 
             }
         }
     },
     getGridBounds:function() {
-        if (!this.grid) return null;
         var topLeftTile = this.grid[0][0];
         var bottomRightTile = this.grid[this.grid.length-1][this.grid[0].length-1];
         return new OpenLayers.Bounds(topLeftTile.bounds.left,