LexerTest memory leak fix-

A new LexerTest unittest introduced a memory leak.  This patch
uses a unique_ptr with a custom deleter to ensure it is properly
deleted.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@305491 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/Lex/LexerTest.cpp

@@ -402,7 +402,9 @@ TEST_F(LexerTest, DontOverallocateStringifyArgs) {
       ArgTokens.push_back(tok);
   }
 
-  MacroArgs *MA = MacroArgs::create(MI, ArgTokens, false, *PP);
+  auto MacroArgsDeleter = [&PP](MacroArgs *M) { M->destroy(*PP); };
+  std::unique_ptr<MacroArgs, decltype(MacroArgsDeleter)> MA(
+      MacroArgs::create(MI, ArgTokens, false, *PP), MacroArgsDeleter);
   Token Result = MA->getStringifiedArgument(0, *PP, {}, {});
   EXPECT_EQ(tok::string_literal, Result.getKind());
   EXPECT_STREQ("\"\\\"StrArg\\\"\"", Result.getLiteralData());