Sprite2d delay loaded issue, another fix attempt! (#1286)

src/Canvas2d/babylon.canvas2d.ts

@@ -1114,10 +1114,6 @@
         private _profilingCanvas: Canvas2D;
         private _profileInfoText: Text2D;
 
-        protected onPrimBecomesDirty() {
-            this._addPrimToDirtyList(this);
-        }
-
         private static _v = Vector3.Zero(); // Must stay zero
         private static _m = Matrix.Identity();
         private static _mI = Matrix.Identity(); // Must stay identity

src/Canvas2d/babylon.renderablePrim2d.ts

@@ -692,7 +692,7 @@
             for (let part of this._instanceDataParts) {
                 let justAllocated = false;
                 // Check if we need to allocate data elements (hidden prim which becomes visible again)
-                if (!part.dataElements && (visChanged || rmChanged)) {
+                if (!part.dataElements && (visChanged || rmChanged || this.isVisible)) {
                     part.allocElements();
                     justAllocated = true;
                 }