Fix for sandboxed OSX filechoosers.

modules/juce_gui_basics/native/juce_mac_FileChooser.mm

@@ -148,6 +148,16 @@ private:
     SilentDummyModalComp dummyModalComponent;
 };
 
+static NSMutableArray* createAllowedTypesArray (const StringArray& filters)
+{
+    NSMutableArray* filterArray = [[[NSMutableArray alloc] init] autorelease];
+
+    for (int i = 0; i < filters.size(); ++i)
+        [filterArray addObject: juceStringToNS (filters[i].replace ("*.", ""))];
+
+    return filterArray;
+}
+
 //==============================================================================
 void FileChooser::showPlatformDialog (Array<File>& results,
                                       const String& title,
@@ -186,6 +196,9 @@ void FileChooser::showPlatformDialog (Array<File>& results,
 
     [panel setTitle: juceStringToNS (title)];
 
+    if (filters->size() != 0)
+        [panel setAllowedFileTypes: createAllowedTypesArray (*filters)];
+
     if (! isSaveDialogue)
     {
         NSOpenPanel* openPanel = (NSOpenPanel*) panel;