Add RandomString() and its test, and use it everywhere it makes sense

test/mac/mach_multiprocess.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #include "test/mac/mach_multiprocess.h"
 
 #include <AvailabilityMacros.h>
 #include <bsm/libbsm.h>
 
 #include <string>
 
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "base/mac/scoped_mach_port.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/rand_util.h"
 #include "gtest/gtest.h"
 #include "test/errors.h"
 #include "test/mac/mach_errors.h"
 #include "util/file/file_io.h"
 #include "util/mach/mach_extensions.h"
 #include "util/mach/mach_message.h"
 #include "util/misc/implicit_cast.h"
+#include "util/misc/random_string.h"
 #include "util/misc/scoped_forbid_return.h"
 
 namespace {
 
 // The “hello” message contains a send right to the child process’ task port.
 struct SendHelloMessage : public mach_msg_base_t {
   mach_msg_port_descriptor_t port_descriptor;
 };
 
 struct ReceiveHelloMessage : public SendHelloMessage {
@@ skipping 42 matching lines @@
 MachMultiprocess::~MachMultiprocess() {
 }
 
 void MachMultiprocess::PreFork() {
   ASSERT_NO_FATAL_FAILURE(Multiprocess::PreFork());
 
   // Set up the parent port and register it with the bootstrap server before
   // forking, so that it’s guaranteed to be there when the child attempts to
   // look it up.
   info_->service_name = "org.chromium.crashpad.test.mach_multiprocess.";
-  for (int index = 0; index < 16; ++index) {
-    info_->service_name.append(1, base::RandInt('A', 'Z'));
-  }
+  info_->service_name.append(RandomString());
 
   info_->local_port = BootstrapCheckIn(info_->service_name);
   ASSERT_TRUE(info_->local_port.is_valid());
 }
 
 mach_port_t MachMultiprocess::LocalPort() const {
   EXPECT_TRUE(info_->local_port.is_valid());
   return info_->local_port.get();
 }
 
@@ skipping 153 matching lines @@
   if (testing::Test::HasFailure()) {
     // Trigger the ScopedForbidReturn destructor.
     return;
   }
 
   forbid_return.Disarm();
 }
 
 }  // namespace test
 }  // namespace crashpad