Faster CryptoRNG.

Author: rkistner

lib/rng.dart

@@ -52,8 +52,12 @@ class CryptoRNG extends RNG {
   Uint8List generateInternal() {
     final b = Uint8List(16);
 
-    for (var i = 0; i < 16; i++) {
-      b[i] = _secureRandom.nextInt(256);
+    for (var i = 0; i < 16; i += 4) {
+      var k = _secureRandom.nextInt(1 << 32);
+      b[i] = k;
+      b[i + 1] = k >> 8;
+      b[i + 2] = k >> 16;
+      b[i + 3] = k >> 24;
     }
 
     return b;