Add way to get native VR UI information from Java

chrome/browser/android/vr_shell/vr_shell_gl.cc

Index: chrome/browser/android/vr_shell/vr_shell_gl.cc
diff --git a/chrome/browser/android/vr_shell/vr_shell_gl.cc b/chrome/browser/android/vr_shell/vr_shell_gl.cc
index 04576097918cdeb873940654a892d8a31229dee4..1023d7539b6b6e1c00d490e9ab9187acb0f49f5b 100644
--- a/chrome/browser/android/vr_shell/vr_shell_gl.cc
+++ b/chrome/browser/android/vr_shell/vr_shell_gl.cc
@@ -6,6 +6,7 @@
 
 #include <chrono>
 #include <limits>
+#include <string>
 #include <utility>
 
 #include "base/android/jni_android.h"
@@ -340,6 +341,18 @@ void VrShellGl::SetSubmitClient(
   submit_client_.Bind(std::move(submit_client_info));
 }
 
+void VrShellGl::CreateUiElementInfos(
+    const std::vector<std::string>& element_names,
+    const base::Callback<void(std::unique_ptr<base::DictionaryValue>)>&
+        on_created) {
+  auto reply = base::MakeUnique<base::DictionaryValue>();
+  for (const auto& name : element_names) {
+    reply->Set(name, std::move(scene_->CreateUiElementInfo(name)));
+  }
+  main_thread_task_runner_->PostTask(
+      FROM_HERE, base::Bind(on_created, base::Passed(std::move(reply))));
+}
+
 void VrShellGl::OnUIFrameAvailable() {
   ui_surface_texture_->UpdateTexImage();
 }