Update StringPrintfTest.Invalid for VS 2015

base/strings/stringprintf_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/strings/stringprintf.h"
 
 #include <errno.h>
 
 #include "base/basictypes.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 130 matching lines @@
   for (int i = 0; i < kBufLen - 1; ++i)
     src[i] = 'a';
   src[kBufLen - 1] = 0;
 
   std::string out;
   SStringPrintf(&out, "%s", src);
 
   EXPECT_STREQ(src, out.c_str());
 }
 
-// TODO(evanm): what's the proper cross-platform test here?
 #if defined(OS_WIN)
-// sprintf in Visual Studio fails when given U+FFFF. This tests that the
-// failure case is gracefuly handled.
+// vswprintf in Visual Studio 2013 fails when given U+FFFF. This tests that the
+// failure case is gracefuly handled. In Visual Studio 2015 the bad character
+// is passed through.
 TEST(StringPrintfTest, Invalid) {
   wchar_t invalid[2];
   invalid[0] = 0xffff;
   invalid[1] = 0;
 
   std::wstring out;
   SStringPrintf(&out, L"%ls", invalid);
+#if _MSC_VER >= 1900
+  EXPECT_STREQ(invalid, out.c_str());
+#else
   EXPECT_STREQ(L"", out.c_str());
+#endif
 }
 #endif
 
 // Test that StringPrintf and StringAppendV do not change errno.
 TEST(StringPrintfTest, StringPrintfErrno) {
   errno = 1;
   EXPECT_EQ("", StringPrintf("%s", ""));
   EXPECT_EQ(1, errno);
   std::string out;
   StringAppendVTestHelper(&out, "%d foo %s", 1, "bar");
   EXPECT_EQ(1, errno);
 }
 
 }  // namespace base