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..2dc324ba53adf24d9f3151031324ad7d752cd63c 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(std::string element_name);

[cjgrant, 2017/03/29 21:16:05]

The parameter should be (const std::string& element_name), to avoid copying the
string.

[bsheedy, 2017/03/29 22:33:44]

Done.

 
   std::vector<const ContentRectangle*> GetWorldElements() const;
   std::vector<const ContentRectangle*> GetHeadLockedElements() const;
@@ -76,6 +78,9 @@ class UiScene {
   float GetBackgroundDistance() const;
   bool GetWebVrRenderingEnabled() const;
 
+  std::unique_ptr<base::DictionaryValue> CreateUiElementInfo(

[cjgrant, 2017/03/29 21:16:06]

Please comment that this is for testing (or name the method as such).

[bsheedy, 2017/03/29 22:33:44]

Done.

+      std::string element_name);
+
  private:
   void ApplyRecursiveTransforms(ContentRectangle* element);
   void ApplyDictToElement(const base::DictionaryValue& dict,