[ChromeOS] Add option to set controlling terminal when launching process.

base/process_util.h

Index: base/process_util.h
diff --git a/base/process_util.h b/base/process_util.h
index 9bcd6d451b51f94d8ad45b8975f50eebfd6294bc..eaa284f765d0b3ebb4867dff15b52dce9830424a 100644
--- a/base/process_util.h
+++ b/base/process_util.h
@@ -225,6 +225,9 @@ struct LaunchOptions {
 #if defined(OS_LINUX)
                   , clone_flags(0)
 #endif  // OS_LINUX
+#if defined(OS_CHROMEOS)
+                  , ctrl_terminal_fd(-1)
+#endif  // OS_CHROMEOS
 #if defined(OS_MACOSX)
                   , synchronize(NULL)
 #endif  // defined(OS_MACOSX)
@@ -282,6 +285,12 @@ struct LaunchOptions {
   int clone_flags;
 #endif  // defined(OS_LINUX)
 
+#if defined(OS_CHROMEOS)
+  // If non-negative, the specified file descriptor will be set as the launched
+  // process' controlling terminal.
+  int ctrl_terminal_fd;
+#endif  // defined(OS_CHROMEOS)
+
 #if defined(OS_MACOSX)
   // When non-NULL, a new LaunchSynchronizationHandle will be created and
   // stored in *synchronize whenever LaunchProcess returns true in the parent