fix a more evil case of : / :: confusion arising in ?:.

llvm-svn: 91039
diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index 54131e0..2536cee 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -317,6 +317,9 @@
     OwningExprResult TernaryMiddle(Actions, true);
     if (NextTokPrec == prec::Conditional) {
       if (Tok.isNot(tok::colon)) {
+        // Don't parse FOO:BAR as if it were a typo for FOO::BAR.
+        ColonProtectionRAIIObject X(*this);
+
         // Handle this production specially:
         //   logical-OR-expression '?' expression ':' conditional-expression
         // In particular, the RHS of the '?' is 'expression', not