Implement a means of letting native VR Shell control the HTML UI.

chrome/browser/android/vr_shell/ui_interface.h

Index: chrome/browser/android/vr_shell/ui_interface.h
diff --git a/chrome/browser/android/vr_shell/ui_interface.h b/chrome/browser/android/vr_shell/ui_interface.h
new file mode 100644
index 0000000000000000000000000000000000000000..a0c5c5069640ec008dbfd2c6f9b9fce8ffa13b95
--- /dev/null
+++ b/chrome/browser/android/vr_shell/ui_interface.h
@@ -0,0 +1,46 @@
+// 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 CHROME_BROWSER_ANDROID_VR_SHELL_UI_INTERFACE_H_
+#define CHROME_BROWSER_ANDROID_VR_SHELL_UI_INTERFACE_H_
+
+#include "base/macros.h"
+#include "base/values.h"
+
+class VrShellUIMessageHandler;
+
+namespace vr_shell {
+
+// This class manages the communication of browser state from VR shell to the
+// HTML UI. State information is asynchronous and unidirectional.
+class UiInterface {
+ public:
+  enum Mode {
+    STANDARD,
+    WEB_VR,
+  };
+
+  UiInterface();
+  virtual ~UiInterface();
+
+  void SetMode(Mode mode);
+  void SetSecureOrigin(bool secure);
+
+  // Called by WebUI when starting VR.
+  void OnDomContentsLoaded();
+  void SetUiMessageHandler(VrShellUIMessageHandler* handler);
+
+ private:
+  void FlushUpdates();
+
+  VrShellUIMessageHandler* handler_;
+  bool loaded_ = false;
+  base::DictionaryValue updates_;
+
+  DISALLOW_COPY_AND_ASSIGN(UiInterface);
+};
+
+}  // namespace vr_shell
+
+#endif  // CHROME_BROWSER_ANDROID_VR_SHELL_UI_INTERFACE_H_