Remove dependency from //mojo to //crypto

mojo/dart/embedder/test/validation_unittest.cc

 // Copyright 2015 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 <stdio.h>
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/path_service.h"
-#include "crypto/random.h"
+#include "base/rand_util.h"
 #include "mojo/dart/embedder/dart_controller.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace mojo {
 namespace dart {
 namespace {
 
 std::string GetPath() {
   base::FilePath path;
   PathService::Get(base::DIR_SOURCE_ROOT, &path);
   path = path.AppendASCII("mojo")
              .AppendASCII("public")
              .AppendASCII("interfaces")
              .AppendASCII("bindings")
              .AppendASCII("tests")
              .AppendASCII("data")
              .AppendASCII("validation");
 
   return path.AsUTF8Unsafe();
 }
 
 static bool generateEntropy(uint8_t* buffer, intptr_t length) {
-  crypto::RandBytes(reinterpret_cast<void*>(buffer), length);
+  base::RandBytes(reinterpret_cast<void*>(buffer), length);
   return true;
 }
 
 static void exceptionCallback(bool* exception, Dart_Handle error) {
   *exception = true;
 }
 
 static void RunTest(const std::string& test) {
   base::FilePath path;
   PathService::Get(base::DIR_SOURCE_ROOT, &path);
@@ skipping 37 matching lines @@
   EXPECT_FALSE(unhandled_exception);
 }
 
 TEST(DartTest, validation) {
   RunTest(GetPath());
 }
 
 }  // namespace
 }  // namespace dart
 }  // namespace mojo