Bug 1732393 - Remove useless include of ServoCSSPropList.h in Document.cpp r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D126552

dom/base/Document.cpp

@@ -102,7 +102,6 @@
 #include "mozilla/SMILTimeContainer.h"
 #include "mozilla/ScopeExit.h"
 #include "mozilla/Components.h"
-#include "mozilla/ServoCSSPropList.h"
 #include "mozilla/ServoStyleConsts.h"
 #include "mozilla/ServoStyleSet.h"
 #include "mozilla/ServoTypes.h"