VR: Avoiding regeneration of RenderText objects for texture rendering

chrome/browser/android/vr_shell/textures/url_bar_texture.h

 // Copyright 2017 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_TEXTURES_URL_BAR_TEXTURE_H_
 #define CHROME_BROWSER_ANDROID_VR_SHELL_TEXTURES_URL_BAR_TEXTURE_H_
 
+#include <memory>
+#include <vector>
+
 #include "chrome/browser/android/vr_shell/textures/ui_texture.h"
+#include "url/gurl.h"
 
-#include "url/gurl.h"
+namespace gfx {
+class RenderText;
+}  // namespace gfx
 
 namespace vr_shell {
 
 class UrlBarTexture : public UiTexture {
  public:
   UrlBarTexture();
   ~UrlBarTexture() override;
   gfx::Size GetPreferredTextureSize(int width) const override;
   gfx::SizeF GetDrawnSize() const override;
 
   void SetHover(bool hover);
   void SetURL(const GURL& gurl);
   void SetSecurityLevel(int level);
 
  private:
   void Draw(SkCanvas* canvas, const gfx::Size& texture_size) override;
   float ToPixels(float meters) const;
 
   gfx::SizeF size_;
   bool hover_ = false;
   int security_level_;
   GURL gurl_;
+  GURL last_drawn_gurl_;
+  std::vector<std::unique_ptr<gfx::RenderText>> gurl_render_texts_;
 };
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_TEXTURES_URL_BAR_TEXTURE_H_