pref entry for Bug 16498 Finished Downloading sound r=varga sr=bz

suite/browser/browser-prefs.js

@@ -89,6 +89,7 @@ pref("browser.show_about_as_stupid_modal_window", false);
 pref("browser.download.progressDnldDialog.keepAlive", true); // keep the dnload progress dialog up after dnload is complete
 pref("browser.download.progressDnldDialog.enable_launch_reveal_buttons", true);
 pref("browser.download.progressDnlgDialog.dontAskForLaunch", false);
+pref("browser.download.finished_sound_url", "");
 
 // various default search settings
 pref("browser.search.defaulturl", "chrome://navigator-region/locale/region.properties");