'constexpr' and 'friend' are both declaration specifiers. Teach the parser this, for better error recovery.

llvm-svn: 166645
diff --git a/clang/test/Parser/recovery.cpp b/clang/test/Parser/recovery.cpp
index ff68758..784002d 100644
--- a/clang/test/Parser/recovery.cpp
+++ b/clang/test/Parser/recovery.cpp
@@ -23,12 +23,15 @@
 struct S {
   int a, b, c;
   S();
+  int x // expected-error {{expected ';'}}
+  friend void f()
 };
 8S::S() : a{ 5 }, b{ 6 }, c{ 2 } { // expected-error {{unqualified-id}}
   return;
 }
 int k;
-int l = k;
+int l = k // expected-error {{expected ';'}}
+constexpr int foo();
 
 5int m = { l }, n = m; // expected-error {{unqualified-id}}