In Parser::SkipUntil do not stop at '@' unconditionally.

Stopping at '@' was originally intended to avoid skipping an '@' at the @interface context
when doing parser recovery, but we should not stop at all '@' tokens because they may be part
of expressions (e.g. in @"string", @selector(), etc.), so in most cases we will want to skip them.

This commit caused 'test/Parser/method-def-in-class.m' to fail for the cases where we tried to
recover from unmatched angle bracket but IMO it is not a big deal to not have good recovery
from such broken code and the way we did recovery would not always work anyway (e.g. if there was '@'
in an expression).

The case that rdar://7029784 is about still passes.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146815 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseObjc.cpp b/lib/Parse/ParseObjc.cpp
index 56d5c57..1f20924 100644
--- a/lib/Parse/ParseObjc.cpp
+++ b/lib/Parse/ParseObjc.cpp
@@ -366,8 +366,12 @@
       allMethods.push_back(methodPrototype);
       // Consume the ';' here, since ParseObjCMethodPrototype() is re-used for
       // method definitions.
-      ExpectAndConsume(tok::semi, diag::err_expected_semi_after_method_proto,
-                       "", tok::semi);
+      if (ExpectAndConsumeSemi(diag::err_expected_semi_after_method_proto)) {
+        // We didn't find a semi and we error'ed out. Skip until a ';' or '@'.
+        SkipUntil(tok::at, /*StopAtSemi=*/true, /*DontConsume=*/true);
+        if (Tok.is(tok::semi))
+          ConsumeToken();
+      }
       continue;
     }
     if (Tok.is(tok::l_paren)) {