Determine test coverage for this case.

content/browser/renderer_host/render_view_host_impl.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/renderer_host/render_view_host_impl.h"
 
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 1029 matching lines @@
   }
 
   storage::FileSystemContext* file_system_context =
       BrowserContext::GetStoragePartition(GetProcess()->GetBrowserContext(),
                                           GetSiteInstance())
           ->GetFileSystemContext();
   filtered_data.file_system_files.clear();
   for (size_t i = 0; i < drop_data.file_system_files.size(); ++i) {
     storage::FileSystemURL file_system_url =
         file_system_context->CrackURL(drop_data.file_system_files[i].url);
-    if (policy->CanReadFileSystemFile(GetProcess()->GetID(), file_system_url))
+    if (policy->CanReadFileSystemFile(GetProcess()->GetID(), file_system_url)) {
+      CHECK(false);
       filtered_data.file_system_files.push_back(drop_data.file_system_files[i]);
+    }
   }
 
   float scale = GetScaleFactorForView(GetWidget()->GetView());
   gfx::ImageSkia image(gfx::ImageSkiaRep(bitmap, scale));
   view->StartDragging(filtered_data, drag_operations_mask, image,
       bitmap_offset_in_dip, event_info);
 }
 
 void RenderViewHostImpl::OnUpdateDragCursor(WebDragOperation current_op) {
   RenderViewHostDelegateView* view = delegate_->GetDelegateView();
@@ skipping 261 matching lines @@
     // Note: We are using the origin URL provided by the sender here. It may be
     // different from the receiver's.
     file_system_file.url =
         GURL(storage::GetIsolatedFileSystemRootURIString(
                  file_system_url.origin(), filesystem_id, std::string())
                  .append(register_name));
   }
 }
 
 }  // namespace content