Add constructors for Float32Array and friends.

client/html/src/Int8Array.dart

Index: client/html/src/Int8Array.dart
diff --git a/client/html/generated/src/interface/Int8Array.dart b/client/html/src/Int8Array.dart
similarity index 62%
rename from client/html/generated/src/interface/Int8Array.dart
rename to client/html/src/Int8Array.dart
index acb8a9c1e4745bb1a3a285e03b44a15086bd7398..0b1a5d45d15ce8d0d3addb9d0792d5265910bc10 100644
--- a/client/html/generated/src/interface/Int8Array.dart
+++ b/client/html/src/Int8Array.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 Int8Array extends ArrayBufferView {
+interface Int8Array extends ArrayBufferView
+    default Int8ArrayWrappingImplementation {
 
   static final int BYTES_PER_ELEMENT = 1;
 
+  Int8Array(int length);
+
+  Int8Array.from(List<num> list);
+
+  Int8Array.fromBuffer(ArrayBuffer buffer);
+
   int get length();
 
   Int8Array subarray(int start, [int end]);