Do some cleanup of file path name handling.

chrome/browser/cocoa/web_drag_source.mm

 // Copyright (c) 2009 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.
 
 #import "chrome/browser/cocoa/web_drag_source.h"
 
 #include "base/file_util.h"
 #include "base/nsimage_cache_mac.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
@@ skipping 34 matching lines @@
 FilePath GetFileNameFromDragData(
     const WebDropData& drop_data, unsigned seq) {
   // Images without ALT text will only have a file extension so we need to
   // synthesize one from the provided extension and URL.
   FilePath file_name([SysUTF16ToNSString(drop_data.file_description_filename)
           fileSystemRepresentation]);
   file_name = file_name.BaseName().RemoveExtension();
 
   if (file_name.empty()) {
     // Retrieve the name from the URL.
-    file_name = FilePath::FromWStringHack(
-        net::GetSuggestedFilename(drop_data.url, "", "", L""));
+    file_name = net::GetSuggestedFilename(drop_data.url, "", "", "");
   }
 
   file_name = file_name.ReplaceExtension([SysUTF16ToNSString(
           drop_data.file_extension) fileSystemRepresentation]);
 
   if (seq > 0) {
     file_name =
         file_name.InsertBeforeExtension(std::string("-")+UintToString(seq));
   }
 
@@ skipping 290 matching lines @@
   if (!dropData_->plain_text.empty())
     [pasteboard_ addTypes:[NSArray arrayWithObject:NSStringPboardType]
                     owner:contentsView_];
 }
 
 - (NSImage*)dragImage {
   return MakeDragImage(dropData_.get());
 }
 
 @end  // @implementation WebDragSource (Private)