Plumb resize notifications around sky/shell

sky/shell/gpu/rasterizer.cc

Index: sky/shell/gpu/rasterizer.cc
diff --git a/sky/shell/gpu/rasterizer.cc b/sky/shell/gpu/rasterizer.cc
index 8e4b49282e31b5a8160008d093aaa46b117bae0b..64e10f274b375d4751483e058d5e30b1598e01d9 100644
--- a/sky/shell/gpu/rasterizer.cc
+++ b/sky/shell/gpu/rasterizer.cc
@@ -34,7 +34,7 @@ base::WeakPtr<Rasterizer> Rasterizer::GetWeakPtr() {
   return weak_factory_.GetWeakPtr();
 }
 
-void Rasterizer::Init(gfx::AcceleratedWidget widget) {
+void Rasterizer::OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget) {
   share_group_ = make_scoped_refptr(new gfx::GLShareGroup());
   surface_ = gfx::GLSurface::CreateViewGLSurface(widget);
   CHECK(surface_) << "GLSurface required.";
@@ -53,6 +53,9 @@ void Rasterizer::Draw(skia::RefPtr<SkPicture> picture) {
   surface_->SwapBuffers();
 }
 
+void Rasterizer::OnDestroyed() {
+}
+
 bool Rasterizer::CreateGLContext() {
   context_ = gfx::GLContext::CreateGLContext(share_group_.get(), surface_.get(),
                                              gfx::PreferIntegratedGpu);