PROTOTYPE (incomplete): Add quad renderer and stub bits to handle security warnings.

chrome/browser/android/vr_shell/vr_shell_renderer.h

Index: chrome/browser/android/vr_shell/vr_shell_renderer.h
diff --git a/chrome/browser/android/vr_shell/vr_shell_renderer.h b/chrome/browser/android/vr_shell/vr_shell_renderer.h
index 98714797e3da986267b1ff2e6dc213ef2804a86c..214c04cc14f4b7e8311b19fb644662030413234b 100644
--- a/chrome/browser/android/vr_shell/vr_shell_renderer.h
+++ b/chrome/browser/android/vr_shell/vr_shell_renderer.h
@@ -37,6 +37,8 @@ enum ShaderID {
   GRADIENT_GRID_FRAGMENT_SHADER,
   CONTROLLER_VERTEX_SHADER,
   CONTROLLER_FRAGMENT_SHADER,
+  SKIA_QUAD_VERTEX_SHADER,
+  SKIA_QUAD_FRAGMENT_SHADER,
   SHADER_ID_MAX
 };
 
@@ -119,6 +121,26 @@ class TexturedQuadRenderer : public BaseQuadRenderer {
   DISALLOW_COPY_AND_ASSIGN(TexturedQuadRenderer);
 };
 
+class SkiaQuadRenderer : public BaseQuadRenderer {
+ public:
+  SkiaQuadRenderer();
+  ~SkiaQuadRenderer() override;
+
+  // Draw the content rect in the texture quad.
+  void Draw(int texture_data_handle,
+               const vr::Mat4f& view_proj_matrix,
+               const gfx::RectF& copy_rect,
+               float opacity);
+
+ private:
+  GLuint model_view_proj_matrix_handle_;
+  GLuint copy_rect_uniform_handle_;
+  GLuint tex_uniform_handle_;
+  GLuint opacity_handle_;
+
+  DISALLOW_COPY_AND_ASSIGN(SkiaQuadRenderer);
+};
+
 // Renders a page-generated stereo VR view.
 class WebVrRenderer : public BaseQuadRenderer {
  public: