Mozart: Implement basic input event dispatch with hit testing.

examples/ui/pdf_viewer/pdf_viewer.cc

 // Copyright 2014 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 <memory>
 #include <string>
 
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 168 matching lines @@
 
     auto update = mojo::gfx::composition::SceneUpdate::New();
     mojo::gfx::composition::ResourcePtr content_resource =
         ganesh_renderer()->DrawCanvas(
             size_,
             base::Bind(&PDFDocumentView::DrawContent, base::Unretained(this)));
     DCHECK(content_resource);
     update->resources.insert(kContentImageResourceId, content_resource.Pass());
 
     auto root_node = mojo::gfx::composition::Node::New();
+    root_node->hit_test_behavior =
+        mojo::gfx::composition::HitTestBehavior::New();
     root_node->op = mojo::gfx::composition::NodeOp::New();
     root_node->op->set_image(mojo::gfx::composition::ImageNodeOp::New());
     root_node->op->get_image()->content_rect = bounds.Clone();
     root_node->op->get_image()->image_resource_id = kContentImageResourceId;
     update->nodes.insert(kRootNodeId, root_node.Pass());
 
     scene()->Update(update.Pass());
     scene()->Publish(nullptr);
   }
 
@@ skipping 96 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(PDFContentViewerApp);
 };
 
 }  // namespace examples
 
 MojoResult MojoMain(MojoHandle application_request) {
   mojo::ApplicationRunnerChromium runner(new examples::PDFContentViewerApp());
   return runner.Run(application_request);
 }