Don't allow '\0' characters in FilePath.

ipc/ipc_message_utils_unittest.cc

Index: ipc/ipc_message_utils_unittest.cc
diff --git a/ipc/ipc_message_utils_unittest.cc b/ipc/ipc_message_utils_unittest.cc
index fe2c4e38e7690c2d9dc0fc2f1082868e0e2aa4a0..ef18a073cee9843cceeb9519ba622361b9136684 100644
--- a/ipc/ipc_message_utils_unittest.cc
+++ b/ipc/ipc_message_utils_unittest.cc
@@ -53,15 +53,17 @@ TEST(IPCMessageUtilsTest, NestedMessages) {
 
 // Tests that detection of various bad parameters is working correctly.
 TEST(IPCMessageUtilsTest, ParameterValidation) {
-  IPC::Message message;
   FilePath::StringType okString(FILE_PATH_LITERAL("hello"), 5);
   FilePath::StringType badString(FILE_PATH_LITERAL("hel\0o"), 5);
-  FilePath okPath(okString);
-  FilePath badPath(badString);
-  ParamTraits<FilePath>::Write(&message, okPath);
-  ParamTraits<FilePath>::Write(&message, badPath);
+
+  // Change this if ParamTraits<FilePath>::Write() changes.
+  IPC::Message message;
+  ParamTraits<FilePath::StringType>::Write(&message, okString);
+  ParamTraits<FilePath::StringType>::Write(&message, badString);
 
   PickleIterator iter(message);
+  FilePath okPath;
+  FilePath badPath;
   ASSERT_TRUE(ParamTraits<FilePath>::Read(&message, &iter, &okPath));
   ASSERT_FALSE(ParamTraits<FilePath>::Read(&message, &iter, &badPath));
 }