Only generate suggested filenames when actually dragging an image.

content/renderer/drop_data_builder.cc

 // Copyright 2013 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/renderer/drop_data_builder.h"
 
 #include <stddef.h>
 
 #include "base/strings/string_util.h"
 #include "content/public/common/drop_data.h"
@@ skipping 40 matching lines @@
           result.html_base_url = item.baseURL;
           break;
         }
         result.custom_data.insert(
             std::make_pair(item.stringType.utf16(), item.stringData.utf16()));
         break;
       }
       case WebDragData::Item::StorageTypeBinaryData:
         result.file_contents.assign(item.binaryData.data(),
                                     item.binaryData.size());
-        result.file_description_filename = item.title.utf16();
+        result.file_contents_source_url = item.binaryDataSourceURL;
+#if defined(OS_WIN)
+        result.file_contents_filename_extension =
+            item.binaryDataFilenameExtension.utf16();
+#else
+        result.file_contents_filename_extension =
+            item.binaryDataFilenameExtension.utf8();

[kinuko, 2017/02/06 22:24:58]

nit: WebStringToFilePath(...).value();

+#endif
+        result.file_contents_content_disposition =
+            item.binaryDataContentDisposition.utf8();
         break;
       case WebDragData::Item::StorageTypeFilename:
         // TODO(varunjain): This only works on chromeos. Support win/mac/gtk.
         result.filenames.push_back(ui::FileInfo(
             blink::WebStringToFilePath(item.filenameData),
             blink::WebStringToFilePath(item.displayNameData)));
         break;
       case WebDragData::Item::StorageTypeFileSystemFile: {
         DropData::FileSystemFileInfo info;
         info.url = item.fileSystemURL;
         info.size = item.fileSystemFileSize;
         info.filesystem_id = item.fileSystemId.ascii();
         result.file_system_files.push_back(info);
         break;
       }
     }
   }
 
   return result;
 }
 
 }  // namespace content