Bug 944537 - Don't send showMessage boolean with Tabs.START event (r=mfinkle)

mobile/android/base/Tabs.java

@@ -447,7 +447,7 @@ public class Tabs implements GeckoEventListener {
                     if ((state & GeckoAppShell.WPL_STATE_START) != 0) {
                         boolean showProgress = message.getBoolean("showProgress");
                         tab.handleDocumentStart(showProgress, message.getString("uri"));
-                        notifyListeners(tab, Tabs.TabEvents.START, showProgress);
+                        notifyListeners(tab, Tabs.TabEvents.START);
                     } else if ((state & GeckoAppShell.WPL_STATE_STOP) != 0) {
                         tab.handleDocumentStop(message.getBoolean("success"));
                         notifyListeners(tab, Tabs.TabEvents.STOP);