Made double-tap zoom work in pinch virtual viewport mode (Chromium-side).

mojo/services/html_viewer/weblayertreeview_impl.cc

Index: mojo/services/html_viewer/weblayertreeview_impl.cc
diff --git a/mojo/services/html_viewer/weblayertreeview_impl.cc b/mojo/services/html_viewer/weblayertreeview_impl.cc
index 3f8ff804255125e530b9d44007e6e768965ff531..92da6481f985dce51b7c5d3430a968de615894aa 100644
--- a/mojo/services/html_viewer/weblayertreeview_impl.cc
+++ b/mojo/services/html_viewer/weblayertreeview_impl.cc
@@ -73,6 +73,18 @@ void WebLayerTreeViewImpl::Layout() {
 }
 
 void WebLayerTreeViewImpl::ApplyViewportDeltas(
+    const gfx::Vector2d& inner_delta,
+    const gfx::Vector2d& outer_delta,
+    float page_scale,
+    float top_controls_delta) {
+  widget_->applyViewportDeltas(
+      inner_delta,
+      outer_delta,
+      page_scale,
+      top_controls_delta);
+}
+
+void WebLayerTreeViewImpl::ApplyViewportDeltas(
     const gfx::Vector2d& scroll_delta,
     float page_scale,
     float top_controls_delta) {