Initial work on a new <view> element backed by a mojo::View.

sky/viewer/document_view.cc

Index: sky/viewer/document_view.cc
diff --git a/sky/viewer/document_view.cc b/sky/viewer/document_view.cc
index 6eafdd25a4b579906eb93bf1136268ac2ca0f2f8..5a955b25aca0d5d4e7f535129566b55bdad101b0 100644
--- a/sky/viewer/document_view.cc
+++ b/sky/viewer/document_view.cc
@@ -151,6 +151,22 @@ blink::WebLayerTreeView* DocumentView::initializeLayerTreeView() {
   return web_layer_tree_view_impl_.get();
 }
 
+void DocumentView::createChildView(const blink::WebURL& url,
+                                   const blink::WebRect& bounds) {
+  if (!root_)
+    return;
+
+  mojo::View* child = mojo::View::Create(root_->view_manager());
+  root_->AddChild(child);

[abarth-chromium, 2014/11/06 22:55:07]

Do we need to observe child so we can destroy it later?

[Matt Perry, 2014/11/06 23:38:50]

I must admit I don't understand the ownership here. Does root_ own its children?
Who owns root_? When we call child->Embed, a new DocumentView is created, whose
root_ node is for some reason different from child.

[Matt Perry, 2014/11/07 17:27:40]

Sky says we need to delete the children manually, because root_ here is a remote
View and will not delete children created locally here. I've added that below.

+  mojo::Rect mojo_bounds;
+  mojo_bounds.x = bounds.x;
+  mojo_bounds.y = bounds.y;
+  mojo_bounds.width = bounds.width;
+  mojo_bounds.height = bounds.height;
+  child->SetBounds(mojo_bounds);
+  child->Embed(mojo::String::From(url.string().utf8()));
+}
+
 void DocumentView::frameDetached(blink::WebFrame* frame) {
   // |frame| is invalid after here.
   frame->close();