C++: Fix resolving of templated partial specialization

Use-case:
template<class T> struct t {};

template<class> struct s { float f; };
template<class X> struct s<t<X>> { int i; };

void f()
{
    s<t<char>> var;
    var.i; // i not highlighted
}

Task-number: QTCREATORBUG-14034
Change-Id: I5d00bc3247352fca4af4c41a47c208ec3e193c8e
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

src/libs/cplusplus/LookupContext.cpp

@@ -1215,6 +1215,13 @@ LookupScopePrivate *LookupScopePrivate::findSpecialization(
 
                 if (specializationTemplateArgument == initializationTemplateArgument)
                     return cit->second;
+
+                if (const NamedType *specName = specializationTemplateArgument->asNamedType()) {
+                    if (const NamedType *initName = initializationTemplateArgument->asNamedType()) {
+                        if (specName->name()->identifier() == initName->name()->identifier())
+                            return cit->second;
+                    }
+                }
             }
         }
     }