Improved loplugin:stringconstant (now that GCC 7 supports it): cppuhelper

Change-Id: I6535fd0cf4f8b906c62fa51cb555da548c6e99ae
Reviewed-on: https://gerrit.libreoffice.org/76688
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

cppuhelper/source/access_control.cxx

@@ -34,7 +34,7 @@ namespace
 {
     OUString str_ac_singleton()
     {
-        return OUString("/singletons/com.sun.star.security.theAccessController");
+        return "/singletons/com.sun.star.security.theAccessController";
     }
 }
 

cppuhelper/source/macro_expander.cxx

@@ -86,7 +86,7 @@ class theImplNames : public rtl::Static<ImplNames, theImplNames> {};
 
 OUString s_impl_name()
 {
-    return OUString(IMPL_NAME);
+    return IMPL_NAME;
 }
 
 Sequence< OUString > const & s_get_service_names()

cppuhelper/source/servicemanager.cxx

@@ -894,8 +894,8 @@ void cppuhelper::ServiceManager::initialize(
 
 OUString cppuhelper::ServiceManager::getImplementationName()
 {
-    return OUString(
-        "com.sun.star.comp.cppuhelper.bootstrap.ServiceManager");
+    return
+        "com.sun.star.comp.cppuhelper.bootstrap.ServiceManager";
 }
 
 sal_Bool cppuhelper::ServiceManager::supportsService(

cppuhelper/source/typemanager.cxx

@@ -1886,8 +1886,8 @@ void cppuhelper::TypeManager::disposing() {} //TODO
 
 OUString cppuhelper::TypeManager::getImplementationName()
 {
-    return OUString(
-        "com.sun.star.comp.cppuhelper.bootstrap.TypeManager");
+    return
+        "com.sun.star.comp.cppuhelper.bootstrap.TypeManager";
 }
 
 sal_Bool cppuhelper::TypeManager::supportsService(