Add constructors for Float32Array and friends.

client/html/src/Int32Array.dart

Index: client/html/src/Int32Array.dart
diff --git a/client/html/generated/src/interface/Int32Array.dart b/client/html/src/Int32Array.dart
similarity index 62%
rename from client/html/generated/src/interface/Int32Array.dart
rename to client/html/src/Int32Array.dart
index 879c57c7edcadbc1ec396e6a031d77345b5139ca..d69bf0c2f30d9e65de721142cf9e2cd1082c678c 100644
--- a/client/html/generated/src/interface/Int32Array.dart
+++ b/client/html/src/Int32Array.dart
@@ -2,12 +2,17 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-// WARNING: Do not edit - generated code.
-
-interface Int32Array extends ArrayBufferView {
+interface Int32Array extends ArrayBufferView
+    default Int32ArrayWrappingImplementation {
 
   static final int BYTES_PER_ELEMENT = 4;
 
+  Int32Array(int length);
+
+  Int32Array.from(List<num> list);
+
+  Int32Array.fromBuffer(ArrayBuffer buffer);
+
   int get length();
 
   Int32Array subarray(int start, [int end]);