clang/test/Tooling/clang-diff-ast.cpp: Satisfy thiscall.

  clang/test/Tooling/clang-diff-ast.cpp:45:12: error: expected string not found in input
   // CHECK: CXXConstructorDecl: X(void (char, int))
             ^
  <stdin>:43:25: note: scanning from here
   AccessSpecDecl: public(42)
                          ^
  <stdin>:44:2: note: possible intended match here
   CXXConstructorDecl: X(void (char, int) __attribute__((thiscall)))(43)
   ^

llvm-svn: 311270