Improve process launch handle sharing API.

components/browser_watcher/watcher_client_win.cc

 // Copyright (c) 2014 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 "components/browser_watcher/watcher_client_win.h"
 
 #include <windows.h>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/process/launch.h"
 #include "base/win/windows_version.h"
 
 namespace browser_watcher {
 
 namespace {
 
 base::Process OpenOwnProcessInheritable() {
   return base::Process(
       ::OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
                     TRUE,  // Ineritable handle.
                     base::GetCurrentProcId()));
 }
 
 }  // namespace
 
 WatcherClient::WatcherClient(const CommandLineGenerator& command_line_generator)
-    : use_legacy_launch_(base::win::GetVersion() < base::win::VERSION_VISTA),
-      command_line_generator_(command_line_generator),
-      process_(base::kNullProcessHandle) {
-}
+    : command_line_generator_(command_line_generator),
+      process_(base::kNullProcessHandle) {}
 
 WatcherClient::~WatcherClient() {
 }
 
 void WatcherClient::LaunchWatcher() {
   DCHECK(!process_.IsValid());
 
   // Build the command line for the watcher process.
   base::Process self = OpenOwnProcessInheritable();
   DCHECK(self.IsValid());
   base::CommandLine cmd_line(command_line_generator_.Run(self.Handle()));
 
-  base::HandlesToInheritVector to_inherit;
   base::LaunchOptions options;
   options.start_hidden = true;
-  if (use_legacy_launch_) {
-    // Launch the child process inheriting all handles on XP.
-    options.inherit_handles = true;
-  } else {
-    // Launch the child process inheriting only |self| on
-    // Vista and better.
-    to_inherit.push_back(self.Handle());
-    to_inherit.insert(to_inherit.end(), inherited_handles_.begin(),
-                      inherited_handles_.end());
-    options.handles_to_inherit = &to_inherit;
-  }
+
+  // Launch the child process inheriting only |self|.
+  options.handles_to_inherit.push_back(self.Handle());
+  options.handles_to_inherit.insert(options.handles_to_inherit.end(),
+                                    inherited_handles_.begin(),
+                                    inherited_handles_.end());
 
   process_ = base::LaunchProcess(cmd_line, options);
   if (!process_.IsValid())
     LOG(ERROR) << "Failed to launch browser watcher.";
 }
 
 void WatcherClient::AddInheritedHandle(HANDLE handle) {
   inherited_handles_.push_back(handle);
 }
 
 }  // namespace browser_watcher