Improved MSVC __interface support by adding first class support for it, instead of aliasing to "struct" which had some incorrect behaviour. Patch by David Robins.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@163013 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 28d8811..bcc9106 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1875,6 +1875,9 @@
         TagName="union" ; FixitTagName = "union " ;TagKind=tok::kw_union ;break;
       case DeclSpec::TST_struct:
         TagName="struct"; FixitTagName = "struct ";TagKind=tok::kw_struct;break;
+      case DeclSpec::TST_interface:
+        TagName="__interface"; FixitTagName = "__interface ";
+        TagKind=tok::kw___interface;break;
       case DeclSpec::TST_class:
         TagName="class" ; FixitTagName = "class " ;TagKind=tok::kw_class ;break;
     }
@@ -2709,6 +2712,7 @@
     // class-specifier:
     case tok::kw_class:
     case tok::kw_struct:
+    case tok::kw___interface:
     case tok::kw_union: {
       tok::TokenKind Kind = Tok.getKind();
       ConsumeToken();
@@ -3531,6 +3535,7 @@
     // struct-or-union-specifier (C99) or class-specifier (C++)
   case tok::kw_class:
   case tok::kw_struct:
+  case tok::kw___interface:
   case tok::kw_union:
     // enum-specifier
   case tok::kw_enum:
@@ -3602,6 +3607,7 @@
     // struct-or-union-specifier (C99) or class-specifier (C++)
   case tok::kw_class:
   case tok::kw_struct:
+  case tok::kw___interface:
   case tok::kw_union:
     // enum-specifier
   case tok::kw_enum:
@@ -3740,6 +3746,7 @@
   case tok::kw_class:
   case tok::kw_struct:
   case tok::kw_union:
+  case tok::kw___interface:
     // enum-specifier
   case tok::kw_enum: