Project: Unify handling of displayName

Unify the handling of displayName with a proper changed signal across
all projects.

Change-Id: I7e503528854b85f6f38de4b0943775f82a0d6123
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/cpptools/modelmanagertesthelper.cpp

@@ -42,13 +42,10 @@ TestProject::TestProject(const QString &name, QObject *parent) :
 {
     setParent(parent);
     setId(Core::Id::fromString(name));
+    setDisplayName(name);
     qRegisterMetaType<QSet<QString> >();
 }
 
-TestProject::~TestProject()
-{
-}
-
 ModelManagerTestHelper::ModelManagerTestHelper(QObject *parent,
                                                bool testOnlyForCleanedProjects)
     : QObject(parent)