[WebSocket] Fix permessage-deflate handshake failure messages.

net/websockets/websocket_basic_handshake_stream.cc

Index: net/websockets/websocket_basic_handshake_stream.cc
diff --git a/net/websockets/websocket_basic_handshake_stream.cc b/net/websockets/websocket_basic_handshake_stream.cc
index a8d12fcb6807cbf8ae15502accbee09ada0777a3..addce34c038cf51254b6145039b92caa79a5e1d6 100644
--- a/net/websockets/websocket_basic_handshake_stream.cc
+++ b/net/websockets/websocket_basic_handshake_stream.cc
@@ -242,7 +242,9 @@ bool ValidatePerMessageDeflateExtension(const WebSocketExtension& extension,
     const std::string& name = it->name();
     if (seen_names.count(name) != 0) {
       *failure_message =
-          "Received duplicate permessage-deflate extension parameter " + name;
+          "Error in permessage-deflate: "

[Adam Rice, 2014/02/10 10:16:14]

There are enough of these that it is probably worth having a little function to
add the prefix and return false, so you can just do

return FormatDeflateError(failure_message, "Received duplicate
permessage-deflate extension parameter " + name);

or similar.

[yhirano, 2014/02/10 12:17:33]

Done.

+          "Received duplicate permessage-deflate extension parameter " +
+          name;
       return false;
     }
     seen_names.insert(name);
@@ -250,33 +252,38 @@ bool ValidatePerMessageDeflateExtension(const WebSocketExtension& extension,
     const bool is_client = (client_or_server == kClientPrefix);
     if (!is_client && client_or_server != kServerPrefix) {
       *failure_message =
+          "Error in permessage-deflate: "
           "Received an unexpected permessage-deflate extension parameter";
       return false;
     }
     const std::string rest(name, kPrefixLen);
     if (rest == kNoContextTakeover) {
       if (it->HasValue()) {
-        *failure_message = "Received invalid " + name + " parameter";
+        *failure_message = "Error in permessage-deflate: Received invalid " +
+                           name + " parameter";
         return false;
       }
       if (is_client)
         params->deflate_mode = WebSocketDeflater::DO_NOT_TAKE_OVER_CONTEXT;
     } else if (rest == kMaxWindowBits) {
       if (!it->HasValue()) {
-        *failure_message = name + " must have value";
+        *failure_message =
+            "Error in permessage-deflate: " + name + " must have value";
         return false;
       }
       int bits = 0;
       if (!base::StringToInt(it->value(), &bits) || bits < 8 || bits > 15 ||
           it->value()[0] == '0' ||
           it->value().find_first_not_of("0123456789") != std::string::npos) {
-        *failure_message = "Received invalid " + name + " parameter";
+        *failure_message = "Error in permessage-deflate: Received invalid " +
+                           name + " parameter";
         return false;
       }
       if (is_client)
         params->client_window_bits = bits;
     } else {
       *failure_message =
+          "Error in permessage-deflate: "
           "Received an unexpected permessage-deflate extension parameter";
       return false;
     }