Implemented FxA

app/utils.js

@@ -151,6 +151,37 @@ function browserName() {
   }
 }
 
+async function streamToArrayBuffer(stream, size) {
+  const reader = stream.getReader();
+  let state = await reader.read();
+
+  if (size) {
+    const result = new Uint8Array(size);
+    let offset = 0;
+    while (!state.done) {
+      result.set(state.value, offset);
+      offset += state.value.length;
+      state = await reader.read();
+    }
+    return result.buffer;
+  }
+
+  const parts = [];
+  let len = 0;
+  while (!state.done) {
+    parts.push(state.value);
+    len += state.value.length;
+    state = await reader.read();
+  }
+  let offset = 0;
+  const result = new Uint8Array(len);
+  for (const part of parts) {
+    result.set(part, offset);
+    offset += part.length;
+  }
+  return result.buffer;
+}
+
 module.exports = {
   fadeOut,
   delay,
@@ -164,5 +195,6 @@ module.exports = {
   loadShim,
   isFile,
   openLinksInNewTab,
-  browserName
+  browserName,
+  streamToArrayBuffer
 };