Fix tab backgrounding on Linux / ChromeOS

base/process_posix.cc

 // Copyright (c) 2008 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 "base/process.h"
 
 #include <sys/types.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 
@@ skipping 39 matching lines @@
   // See SetProcessBackgrounded().
   return false;
 }
 
 bool Process::SetProcessBackgrounded(bool value) {
   // POSIX only allows lowering the priority of a process, so if we
   // were to lower it we wouldn't be able to raise it back to its initial
   // priority.
   return false;
 }
+
+// static
+bool Process::CanBackgroundProcesses() {
+  return false;
+}
+
 #endif
 
 int Process::GetPriority() const {
   DCHECK(process_);
   return getpriority(PRIO_PROCESS, process_);
 }
 
 }  // namspace base