Creates BackgroundShell and uses it in test

BackgroundShell creates the necessary mojo state in a background
thread and then vends an ApplicationImpl to the main thread so that
the main thread can use mojo.

I also converted views_apptests to a unittest that makes use of
BackgroundShell.

BUG=577242, 577274
TEST=none
R=ben@chromium.org

Review URL: https://codereview.chromium.org/1667273002

Cr-Commit-Position: refs/heads/master@{#374156}

1 files changed, 43 insertions, 0 deletions

diff --git a/mojo/shell/background/background_shell.h b/mojo/shell/background/background_shell.h
new file mode 100644
index 0000000..ce68649
--- /dev/null
+++ b/mojo/shell/background/background_shell.h
@@ -0,0 +1,43 @@
+// Copyright 2016 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.
+
+#ifndef MOJO_SHELL_BACKGROUND_BACKGROUND_SHELL_H_
+#define MOJO_SHELL_BACKGROUND_BACKGROUND_SHELL_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "mojo/public/cpp/bindings/interface_request.h"
+#include "mojo/shell/public/interfaces/application.mojom.h"
+
+class GURL;
+
+namespace mojo {
+namespace shell {
+
+// BackgroundShell starts up the mojo shell on a background thread, and
+// destroys the thread in the destructor. Once created use CreateApplication()
+// to obtain an InterfaceRequest for the Application. The InterfaceRequest can
+// then be bound to an ApplicationImpl.
+class BackgroundShell {
+ public:
+  BackgroundShell();
+  ~BackgroundShell();
+
+  void Init();
+
+  // Obtains an InterfaceRequest for the specified url.
+  InterfaceRequest<mojom::Application> CreateApplication(const GURL& url);
+
+ private:
+  class MojoThread;
+
+  scoped_ptr<MojoThread> thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(BackgroundShell);
+};
+
+}  // namespace shell
+}  // namespace mojo
+
+#endif  // MOJO_SHELL_BACKGROUND_BACKGROUND_SHELL_H_