Add way to get native VR UI information from Java

chrome/browser/android/vr_shell/ui_scene.h

Index: chrome/browser/android/vr_shell/ui_scene.h
diff --git a/chrome/browser/android/vr_shell/ui_scene.h b/chrome/browser/android/vr_shell/ui_scene.h
index 4bcb6d88d29a490db659f71ee6a5720adfad48f4..d57e851b0c7d49743594d627ad0fef2fb3ed6479 100644
--- a/chrome/browser/android/vr_shell/ui_scene.h
+++ b/chrome/browser/android/vr_shell/ui_scene.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_ANDROID_VR_SHELL_UI_SCENE_H_
 
 #include <memory>
+#include <string>
 #include <vector>
 
 #include "base/macros.h"
@@ -67,6 +68,7 @@ class UiScene {
   const std::vector<std::unique_ptr<ContentRectangle>>& GetUiElements() const;
 
   ContentRectangle* GetUiElementById(int element_id);
+  ContentRectangle* GetUiElementByName(const std::string& element_name);
 
   std::vector<const ContentRectangle*> GetWorldElements() const;
   std::vector<const ContentRectangle*> GetHeadLockedElements() const;
@@ -76,6 +78,12 @@ class UiScene {
   float GetBackgroundDistance() const;
   bool GetWebVrRenderingEnabled() const;
 
+  // Builds a dictionary of the given element's properties for testing
+  // purposes. This dictionary can be serialized and passed back to Java
+  // during end-to-end testing.
+  std::unique_ptr<base::DictionaryValue> CreateUiElementInfo(
+      const std::string& element_name);
+
  private:
   void ApplyRecursiveTransforms(ContentRectangle* element);
   void ApplyDictToElement(const base::DictionaryValue& dict,