Expose some sky_viewer plumbing to allow for reuse

sky/viewer/content_handler_impl.cc

Index: sky/viewer/content_handler_impl.cc
diff --git a/sky/viewer/content_handler_impl.cc b/sky/viewer/content_handler_impl.cc
index b36e4f7cbdc66e0cd07a0be2a9ea2a565da58dc8..b917b41eb64fd7a203ea22bf999cebfe1038c29b 100644
--- a/sky/viewer/content_handler_impl.cc
+++ b/sky/viewer/content_handler_impl.cc
@@ -10,6 +10,7 @@
 #include "mojo/public/cpp/utility/run_loop.h"
 #include "mojo/services/network/public/interfaces/network_service.mojom.h"
 #include "sky/viewer/document_view.h"
+#include "sky/viewer/sky_loader.h"
 
 namespace sky {
 
@@ -24,36 +25,14 @@ class SkyApplication : public mojo::Application {
                   mojo::Array<mojo::String> args,
                   const mojo::String& url) override {
     shell_ = shell.Pass();
-    mojo::ServiceProviderPtr service_provider;
-    shell_->ConnectToApplication("mojo:network_service",
-                                 mojo::GetProxy(&service_provider), nullptr);
-    mojo::ConnectToService(service_provider.get(), &network_service_);
+    sky_loader_.reset(new SkyLoader(shell_.get(), initial_response_.Pass()));
   }
 
   void AcceptConnection(const mojo::String& requestor_url,
                         mojo::InterfaceRequest<mojo::ServiceProvider> services,
                         mojo::ServiceProviderPtr exposed_services,
                         const mojo::String& url) override {
-    if (initial_response_) {
-      OnResponseReceived(mojo::URLLoaderPtr(), services.Pass(),
-                         exposed_services.Pass(), initial_response_.Pass());
-    } else {
-      mojo::URLLoaderPtr loader;
-      network_service_->CreateURLLoader(mojo::GetProxy(&loader));
-      mojo::URLRequestPtr request(mojo::URLRequest::New());
-      request->url = url;
-      request->auto_follow_redirects = true;
-
-      // |loader| will be pass to the OnResponseReceived method through a
-      // callback. Because order of evaluation is undefined, a reference to the
-      // raw pointer is needed.
-      mojo::URLLoader* raw_loader = loader.get();
-      raw_loader->Start(
-          request.Pass(),
-          base::Bind(&SkyApplication::OnResponseReceived,
-                     base::Unretained(this), base::Passed(&loader),
-                     base::Passed(&services), base::Passed(&exposed_services)));
-    }
+    sky_loader_->LoadApplication(services.Pass(), exposed_services.Pass(), url);
   }
 
   void RequestQuit() override {
@@ -61,19 +40,10 @@ class SkyApplication : public mojo::Application {
   }
 
  private:
-  void OnResponseReceived(
-      mojo::URLLoaderPtr loader,
-      mojo::InterfaceRequest<mojo::ServiceProvider> services,
-      mojo::ServiceProviderPtr exposed_services,
-      mojo::URLResponsePtr response) {
-    new DocumentView(services.Pass(), exposed_services.Pass(), response.Pass(),
-                     shell_.get());
-  }
-
   mojo::StrongBinding<mojo::Application> binding_;
   mojo::ShellPtr shell_;
-  mojo::NetworkServicePtr network_service_;
   mojo::URLResponsePtr initial_response_;
+  scoped_ptr<SkyLoader> sky_loader_;
 };
 
 ContentHandlerImpl::ContentHandlerImpl(