base: Remove the string logging from CHECK().

chromeos/network/onc/onc_utils_unittest.cc

Index: chromeos/network/onc/onc_utils_unittest.cc
diff --git a/chromeos/network/onc/onc_utils_unittest.cc b/chromeos/network/onc/onc_utils_unittest.cc
index a8577b15c380ed1a09df8c73ae031ee774223cee..c024bdaed1ad661b9444a455f5ed717d126944e6 100644
--- a/chromeos/network/onc/onc_utils_unittest.cc
+++ b/chromeos/network/onc/onc_utils_unittest.cc
@@ -33,8 +33,7 @@ std::unique_ptr<base::Value> ReadTestJson(const std::string& filename) {
                                          base::JSON_ALLOW_TRAILING_COMMAS);
   std::string error_message;
   result = deserializer.Deserialize(nullptr, &error_message);
-  CHECK(result != nullptr) << "Couldn't json-deserialize file: " << filename
-                           << ": " << error_message;
+  CHECK(result != nullptr);
   return result;
 }