Align to nsWidgetInitData changes

I do hope that we don't need to do gludges for OMTC now.

Commit:  8a9daf3
Author:  David Anderson <danderson@mozilla.com>
Date:    (1 year, 7 months ago) 2015-05-12 01:26:01 -0400
Subject: Enable APZ for all Desktop windows if E10s is enabled. (bug 1163115, r=kats)

embedding/embedlite/embedshared/EmbedLiteWindowBaseChild.cpp

@@ -155,7 +155,6 @@ void EmbedLiteWindowBaseChild::CreateWidget()
   nsWidgetInitData  widgetInit;
   widgetInit.clipChildren = true;
   widgetInit.mWindowType = eWindowType_toplevel;
-  widgetInit.mRequireOffMainThreadCompositing = true;
 
   // EmbedLitePuppetWidget::CreateCompositor() reads back Size
   // when it creates the compositor.