Teach SkyView code path to print hello, world

sky/shell/ui/engine.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sky/shell/ui/engine.h"
 
 #include "base/bind.h"
 #include "base/trace_event/trace_event.h"
 #include "mojo/public/cpp/application/connect.h"
 #include "sky/engine/public/platform/WebInputEvent.h"
@@ skipping 52 matching lines @@
 }
 
 void Engine::BeginFrame(base::TimeTicks frame_time) {
   TRACE_EVENT0("sky", "Engine::BeginFrame");
 
   double frame_time_sec = (frame_time - base::TimeTicks()).InSecondsF();
   double deadline_sec = frame_time_sec;
   double interval_sec = 1.0 / 60;
   blink::WebBeginFrameArgs args(frame_time_sec, deadline_sec, interval_sec);
 
-  web_view_->beginFrame(args);
-  web_view_->layout();
+  if (web_view_) {
+    web_view_->beginFrame(args);
+    web_view_->layout();
+  }
 }
 
 skia::RefPtr<SkPicture> Engine::Paint() {
   TRACE_EVENT0("sky", "Engine::Paint");
 
   SkRTreeFactory factory;
   SkPictureRecorder recorder;
   auto canvas = skia::SharePtr(recorder.beginRecording(
       physical_size_.width(), physical_size_.height(), &factory,
       SkPictureRecorder::kComputeSaveLayerInfo_RecordFlag));
 
-  web_view_->paint(canvas.get(), blink::WebRect(gfx::Rect(physical_size_)));
+  if (web_view_)
+    web_view_->paint(canvas.get(), blink::WebRect(gfx::Rect(physical_size_)));
+
   return skia::AdoptRef(recorder.endRecordingAsPicture());
 }
 
 void Engine::ConnectToViewportObserver(
     mojo::InterfaceRequest<ViewportObserver> request) {
   viewport_observer_binding_.Bind(request.Pass());
 }
 
 void Engine::OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget) {
   config_.gpu_task_runner->PostTask(
@@ skipping 39 matching lines @@
 void Engine::OnInputEvent(InputEventPtr event) {
   TRACE_EVENT0("sky", "Engine::OnInputEvent");
   scoped_ptr<blink::WebInputEvent> web_event =
       ConvertEvent(event, device_pixel_ratio_);
   if (!web_event)
     return;
   web_view_->handleInputEvent(*web_event);
 }
 
 void Engine::LoadURL(const mojo::String& url) {
+  // Enable SkyView here.
+  if (false) {
+    sky_view_ = blink::SkyView::Create();
+    sky_view_->Load(GURL(url));
+    return;
+  }
+
   // 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));
 }
 
@@ skipping 32 matching lines @@
 
 void Engine::DidNavigateLocally(const mojo::String& url) {
 }
 
 void Engine::RequestNavigateHistory(int32_t delta) {
   NOTIMPLEMENTED();
 }
 
 }  // namespace shell
 }  // namespace sky