Added support for C++11 type-alias type declarations.

In the future, we might want to add a TypeAliasDecl AST node,
but for now this simple approach is enough for typedef-like using declarations.

Won't be enough to support partial template using syntax (TypeAliasTemplateDecl).

Partial fix for https://github.com/mono/CppSharp/issues/664.

src/CppParser/Parser.cpp

@@ -3184,8 +3184,9 @@ Declaration* Parser::WalkDeclaration(const clang::Decl* D,
         break;
     }
     case Decl::Typedef:
+    case Decl::TypeAlias:
     {
-        auto TD = cast<clang::TypedefDecl>(D);
+        auto TD = cast<clang::TypedefNameDecl>(D);
 
         auto NS = GetNamespace(TD);
         auto Name = GetDeclName(TD);

tests/Common/Common.Tests.cs

@@ -383,6 +383,8 @@ public class CommonTests : GeneratorTestFixture
     {
         var ret = common.Function();
         Assert.That(ret, Is.EqualTo(5));
+
+        common.FuncWithTypeAlias(0);
     }
 
     [Test]

tests/Common/Common.cpp

@@ -618,3 +618,7 @@ HasProtectedEnum::HasProtectedEnum()
 void HasProtectedEnum::function(ProtectedEnum param)
 {
 }
+
+void FuncWithTypeAlias(custom_int_t i)
+{
+}

tests/Common/Common.h

@@ -1103,6 +1103,9 @@ protected:
     void function(ProtectedEnum param);
 };
 
+using custom_int_t = int;
+void FuncWithTypeAlias(custom_int_t i);
+
 struct TestsTypes
 {
     int(*FunctionNoProto)();