Ensure proper response to chrome client_max_window_bits

sdk/lib/io/websocket.dart

Index: sdk/lib/io/websocket.dart
diff --git a/sdk/lib/io/websocket.dart b/sdk/lib/io/websocket.dart
index 5170bde89e6e45766c476c44122db6333be93f6f..7a6b86968bf02aa5ce81055bdacdc6c8061876b0 100644
--- a/sdk/lib/io/websocket.dart
+++ b/sdk/lib/io/websocket.dart
@@ -84,7 +84,10 @@ class CompressionOptions {
     var info = new List(2);
 
     int mwb;
-    var part = requested.parameters[_serverMaxWindowBits];
+    String part;
+    if (requested?.parameters != null) {
+      part = requested.parameters[_serverMaxWindowBits];
+    }
     if (part != null) {
       if (part.length >= 2 && part.startsWith('0')) {
         throw new ArgumentError("Illegal 0 padding on value.");
@@ -97,21 +100,22 @@ class CompressionOptions {
         info[1] = mwb;
       }
     } else {
+      info[0] = "";
       info[1] = _WebSocketImpl.DEFAULT_WINDOW_BITS;
     }
     return info;
   }
 
   /// Returns default values for client compression request headers.
-  List _createClientRequestHeader(HeaderValue requested) {
-    var info = new List(2);
+  List _createClientRequestHeader(HeaderValue requested, int size) {

[Søren Gjesse, 2015/11/11 13:31:08]

This is no longer returning a List.

[butlermatt, 2015/11/11 18:26:30]

Done.

+    var info = "";
 
-    info[1] = _WebSocketImpl.DEFAULT_WINDOW_BITS;
-    if (requested != null &&
-        requested.parameters[_clientMaxWindowBits] != null) {
-      info[0] = "; client_max_window_bits=${info[1]}";
+    // If responding to a valid request, specify size
+    if (requested != null) {
+      info = "; client_max_window_bits=$size";
     } else {
-      info[0] = "; client_max_window_bits";
+      // Client request. Specify default
+      info = "; client_max_window_bits";
     }
 
     return info;
@@ -141,19 +145,14 @@ class CompressionOptions {
       header += "; server_no_context_takeover";
     }
 
-    if (requested == null ||
-        requested.parameters.containsKey(_clientMaxWindowBits)) {
-      var clientList = _createClientRequestHeader(requested);
-      header += clientList[0];
-      info[1] = clientList[1];
-    } else {
-      var headerList = _createServerResponseHeader(requested);
-      header += headerList[0];
-      info[1] = headerList[1];
-    }
+    var headerList = _createServerResponseHeader(requested);
+    header += headerList[0];
+    info[1] = headerList[1];
 
-    info[0] = header;
+    var clientList = _createClientRequestHeader(requested, info[1]);
+    header += clientList;
 
+    info[0] = header;
     return info;
   }
 }