Fixed standard rendering pipeline depth map require

src/PostProcess/RenderPipeline/Pipelines/babylon.standardRenderingPipeline.ts

@@ -726,9 +726,8 @@
         }
 
         private _getDepthTexture(): Texture {
-            var geometry = this._scene.enableGeometryBufferRenderer();
-            if (geometry) {
-                return geometry.getGBuffer().textures[0];
+            if (this._scene.getEngine().getCaps().drawBuffersExtension) {
+                return this._scene.enableGeometryBufferRenderer().getGBuffer().textures[0];
             }
 
             return this._scene.enableDepthRenderer().getDepthMap();