Make WebView::close not crash and start to fix navigation in SkyShell

sky/shell/ui/engine.cc

Index: sky/shell/ui/engine.cc
diff --git a/sky/shell/ui/engine.cc b/sky/shell/ui/engine.cc
index e8b6560e8acb863017db49d69f5643281ba4bb60..9333a41562f06f4095d91f98c42bfc94126de604 100644
--- a/sky/shell/ui/engine.cc
+++ b/sky/shell/ui/engine.cc
@@ -119,13 +119,21 @@ void Engine::OnInputEvent(InputEventPtr event) {
 }
 
 void Engine::LoadURL(const mojo::String& url) {
-  web_view_ = blink::WebView::create(this);
+  // Something bad happens if you try to call WebView::close and replace
+  // the webview.  So for now we just load into the existing one. :/
+  if (!web_view_)
+    web_view_ = blink::WebView::create(this);
   ConfigureSettings(web_view_->settings());
   web_view_->setMainFrame(blink::WebLocalFrame::create(this));
   UpdateWebViewSize();
   web_view_->mainFrame()->load(GURL(url));
 }
 
+void Engine::frameDetached(blink::WebFrame* frame) {
+  // |frame| is invalid after here.
+  frame->close();
+}
+
 void Engine::initializeLayerTreeView() {
 }
 
@@ -133,5 +141,23 @@ void Engine::scheduleVisualUpdate() {
   animator_->RequestFrame();
 }
 
+blink::ServiceProvider* Engine::services() {
+  return this;
+}
+
+mojo::NavigatorHost* Engine::NavigatorHost() {
+  return this;
+}
+
+void Engine::RequestNavigate(mojo::Target target,
+                             mojo::URLRequestPtr request) {
+  // Ignoring target for now.
+  base::MessageLoop::current()->PostTask(FROM_HERE,
+      base::Bind(&Engine::LoadURL, GetWeakPtr(), request->url));
+}
+
+void Engine::DidNavigateLocally(const mojo::String& url) {
+}
+
 }  // namespace shell
 }  // namespace sky