[gtk] Fix file filter bug for <input type=file accept=mime/type>.

chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc

Index: chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
diff --git a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
index a48d45056ce336626b47a20a8773f40e6aee1ed2..6b5f6420d437c45332e19e6372cf9d2af170ff9b 100644
--- a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
+++ b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
@@ -49,6 +49,18 @@ void SetGtkTransientForAura(GtkWidget* dialog, aura::Window* parent) {
   g_object_set_data(G_OBJECT(dialog), kAuraTransientParent, parent);
 }
 
+// Makes sure that .jpg also shows .JPG. |data| is a std::string* in disguise.
+gboolean FileFilterCaseInsensitive(const GtkFileFilterInfo* file_info,
+                                   gpointer data) {
+  std::string* file_extension = reinterpret_cast<std::string*>(data);
+  return EndsWith(file_info->filename, *file_extension, false);
+}
+
+// Deletes |data| when gtk_file_filter_add_custom() is done with it.
+void OnFileFilterDataDestroyed(gpointer data) {
+  delete reinterpret_cast<std::string*>(data);
+}
+
 }  // namespace
 
 namespace libgtk2ui {
@@ -272,9 +284,14 @@ void SelectFileDialogImplGTK::AddFilters(GtkFileChooser* chooser) {
       if (!current_extension.empty()) {
         if (!filter)
           filter = gtk_file_filter_new();
-        std::string pattern = "*." + current_extension;
-        gtk_file_filter_add_pattern(filter, pattern.c_str());
-        fallback_labels.insert(pattern);
+        // |file_extension| is freed in |OnFileFilterDataDestroyed()|.
+        std::string* file_extension = new std::string("." + current_extension);
+        gtk_file_filter_add_custom(filter,
+                                   GTK_FILE_FILTER_FILENAME,
+                                   &FileFilterCaseInsensitive,
+                                   reinterpret_cast<gpointer>(file_extension),
+                                   &OnFileFilterDataDestroyed);
+        fallback_labels.insert(std::string("*").append(*file_extension));
       }
     }
     // We didn't find any non-empty extensions to filter on.