Fix PDF Viewer control loading at HiDPI scale factors

chrome/renderer/pepper/ppb_pdf_impl.cc

Index: chrome/renderer/pepper/ppb_pdf_impl.cc
diff --git a/chrome/renderer/pepper/ppb_pdf_impl.cc b/chrome/renderer/pepper/ppb_pdf_impl.cc
index cdf787c006530994f38795c9f9fbf86e6e2f420b..057d0a6143484bd0f4b97a5712344edd9df7ca6c 100644
--- a/chrome/renderer/pepper/ppb_pdf_impl.cc
+++ b/chrome/renderer/pepper/ppb_pdf_impl.cc
@@ -349,12 +349,12 @@ PP_Resource GetResourceImageForScale(PP_Instance instance_id,
   if (!content::GetHostGlobals()->GetInstance(instance_id))
     return 0;
 
-  if (!res_image_skia->HasRepresentation(scale_factor))
-    return 0;
-
   gfx::ImageSkiaRep image_skia_rep = res_image_skia->GetRepresentation(
       scale_factor);
 
+  if (image_skia_rep.is_null() || image_skia_rep.scale_factor() != scale_factor)
+    return 0;
+
   scoped_refptr<webkit::ppapi::PPB_ImageData_Impl> image_data(
       new webkit::ppapi::PPB_ImageData_Impl(
           instance_id,