Clear the clipboard closing Incognito window

ui/base/clipboard/scoped_clipboard_writer.h

Index: ui/base/clipboard/scoped_clipboard_writer.h
diff --git a/ui/base/clipboard/scoped_clipboard_writer.h b/ui/base/clipboard/scoped_clipboard_writer.h
index 576922bdf2c80ea515ed0cc8b67617326d34de3e..04f09d35378c0429d7eb7994888afb89b36b33e6 100644
--- a/ui/base/clipboard/scoped_clipboard_writer.h
+++ b/ui/base/clipboard/scoped_clipboard_writer.h
@@ -30,6 +30,10 @@ class UI_EXPORT ScopedClipboardWriter {
   // Create an instance that is a simple wrapper around clipboard.
   ScopedClipboardWriter(Clipboard* clipboard, Clipboard::Buffer buffer);
 
+  ScopedClipboardWriter(Clipboard* clipboard,
+                        Clipboard::Buffer buffer,
+                        Clipboard::SourceTag source_tag);
+
   ~ScopedClipboardWriter();
 
   // Converts |text| to UTF-8 and adds it to the clipboard.
@@ -78,6 +82,7 @@ class UI_EXPORT ScopedClipboardWriter {
   Clipboard::ObjectMap objects_;
   Clipboard* clipboard_;
   Clipboard::Buffer buffer_;
+  Clipboard::SourceTag source_tag_;
 
   // We keep around the UTF-8 text of the URL in order to pass it to
   // Clipboard::DidWriteURL().