Apply viewport to dip scale to Graphics2D, Compositor

content/renderer/pepper/pepper_graphics_2d_host.h

Index: content/renderer/pepper/pepper_graphics_2d_host.h
diff --git a/content/renderer/pepper/pepper_graphics_2d_host.h b/content/renderer/pepper/pepper_graphics_2d_host.h
index 32b59ab10cf50b6b9d0e1c85f1dd413b3144e103..6fb01c29e8f483d7cda51956ad680540b8310191 100644
--- a/content/renderer/pepper/pepper_graphics_2d_host.h
+++ b/content/renderer/pepper/pepper_graphics_2d_host.h
@@ -94,6 +94,11 @@ class CONTENT_EXPORT PepperGraphics2DHost
 
   void ClearCache();
 
+  void set_viewport_to_dip_scale(float viewport_to_dip_scale) {
+    DCHECK_LT(0, viewport_to_dip_scale_);
+    viewport_to_dip_scale_ = viewport_to_dip_scale;
+  }
+
  private:
   PepperGraphics2DHost(RendererPpapiHost* host,
                        PP_Instance instance,
@@ -203,6 +208,9 @@ class CONTENT_EXPORT PepperGraphics2DHost
   // DIP
   float scale_;
 
+  // The scale between the viewport and dip.
+  float viewport_to_dip_scale_ = 1.0f;
+
   ppapi::host::ReplyMessageContext flush_reply_context_;
 
   bool is_running_in_process_;