Move crypto_helpers from sync to base

chrome/common/random_unittest.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+#include "chrome/common/random.h"
+
+TEST(SyncRandomTest, Generate128BitRandomBase64String) {
+  std::string random_string = Generate128BitRandomBase64String();
+  EXPECT_EQ(24U, random_string.size());
+  char accumulator = 0;
+  for (size_t i = 0; i < random_string.size(); ++i)
+    accumulator |= random_string[i];
+  // In theory this test can fail, but it won't before the universe dies of
+  // heat death.
+  EXPECT_NE(0, accumulator);
+}