PR14296: function parameter name collisions in function try/catch

C++11 3.3.3/2 "A parameter name shall not be redeclared in the outermost block
of the function definition nor in the outermost block of any handler associated
with a function-try-block."

It's not totally clear to me whether the "FIXME" case is covered by this, but
Richard Smith thinks it probably should be. It's just a bit more involved to
fix that case.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@167650 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/IdentifierResolver.cpp b/lib/Sema/IdentifierResolver.cpp
index 4d62cab..50413c3 100644
--- a/lib/Sema/IdentifierResolver.cpp
+++ b/lib/Sema/IdentifierResolver.cpp
@@ -135,8 +135,13 @@
       // of the controlled statement.
       //
       assert(S->getParent() && "No TUScope?");
-      if (S->getParent()->getFlags() & Scope::ControlScope)
+      if (S->getFlags() & Scope::FnTryScope)
         return S->getParent()->isDeclScope(D);
+      if (S->getParent()->getFlags() & Scope::ControlScope) {
+        if (S->getParent()->getFlags() & Scope::FnCatchScope)
+          S = S->getParent();
+        return S->getParent()->isDeclScope(D);
+      }
     }
     return false;
   }