Reformats how auth message is converted to string for logging, so it doesn't...

Reformats how auth message is converted to string for logging, so it doesn't log binary data and prints on one line.

TESTED=chrome --vmodule="cast_auth*=1"
BUG=365452

Review URL: https://codereview.chromium.org/250713002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@266705 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/extensions/api/cast_channel/cast_message_util.cc

@@ -107,17 +107,18 @@ std::string CastMessageToString(const CastMessage& message_proto) {
 std::string AuthMessageToString(const DeviceAuthMessage& message) {
   std::string out("{");
   if (message.has_challenge()) {
-    out += "\n  challenge = {},";
+    out += "challenge: {}, ";
   }
   if (message.has_response()) {
-    out += "\n  response = {";
-    out += "\n    signature = " + message.response().signature();
-    out += "\n,   certificate = " +
-        message.response().client_auth_certificate();
-    out += "\n  }";
+    out += "response: {signature: (";
+    out += base::UintToString(message.response().signature().length());
+    out += " bytes), certificate: (";
+    out += base::UintToString(
+        message.response().client_auth_certificate().length());
+    out += " bytes)}";
   }
   if (message.has_error()) {
-    out += "\n  error = {";
+    out += ", error: {";
     out += base::IntToString(message.error().error_type());
     out += "}";
   }