[Linux] Use PR_SET_NO_NEW_PRIVS by default in base/process/launch.h.

chrome/browser/sessions/session_restore_browsertest.cc

Index: chrome/browser/sessions/session_restore_browsertest.cc
diff --git a/chrome/browser/sessions/session_restore_browsertest.cc b/chrome/browser/sessions/session_restore_browsertest.cc
index 25c306d05b56fa934e3a47a0ef0d5325b16fc749..9ff6d504fa1c04df8eb5e0cb093e8ddd0749c757 100644
--- a/chrome/browser/sessions/session_restore_browsertest.cc
+++ b/chrome/browser/sessions/session_restore_browsertest.cc
@@ -923,7 +923,14 @@ IN_PROC_BROWSER_TEST_F(SessionRestoreTest,
 
   ui_test_utils::BrowserAddedObserver window_observer;
 
-  base::LaunchProcess(app_launch_arguments, base::LaunchOptions(), NULL);
+  base::LaunchOptions options;
+#if defined(OS_LINUX)
+  // To prevent accidental privilege sharing to an untrusted child, processes
+  // are started with PR_SET_NO_NEW_PRIVS. Do not set that here, since this
+  // new child will be a test browser process.
+  options.allow_new_privs = true;
+#endif
+  base::LaunchProcess(app_launch_arguments, options, NULL);
 
   Browser* app_window = window_observer.WaitForSingleNewBrowser();
   ASSERT_EQ(2u, active_browser_list_->size());