Fix CompiledData::CompilationUnit object leak
Fix CompiledData::CompilationUnit object leak

Don't ref CompiledData::CompilationUnit in constructor of ScriptFunction
since its has been referenced in its base class

Change-Id: I9ad2d6e190c2ac11de4ccd63015c81d2dead3971
Reviewed-by: Simon Hausmann <a975102812d593b3191088e3d0aeaeb6f11dbcf5@digia.com>

qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative,mgrunditz/qtdeclarative-2d,qmlc/qtdeclarative