Update internal state on undo to avoid a crash.

chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc

Index: chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc
diff --git a/chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc b/chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc
index c96a1888e70c1da36cb02ce8cdbe008d2fa9c7f7..b207ad0c3a4984f6b1467a781a5f222fafae8d55 100644
--- a/chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc
+++ b/chrome/browser/autocomplete/autocomplete_edit_view_gtk.cc
@@ -1702,8 +1702,10 @@ void AutocompleteEditViewGtk::SavePrimarySelection(
 
 void AutocompleteEditViewGtk::SetTextAndSelectedRange(const std::wstring& text,
                                                       const CharRange& range) {
-  std::string utf8 = WideToUTF8(text);
-  gtk_text_buffer_set_text(text_buffer_, utf8.data(), utf8.length());
+  if (text != GetText()) {
+    std::string utf8 = WideToUTF8(text);
+    gtk_text_buffer_set_text(text_buffer_, utf8.data(), utf8.length());
+  }
   SetSelectedRange(range);
   AdjustTextJustification();
 }