Bug 844323 - Part 2a: Make the in-process ProcessPriorityManager handle <iframe mozbrowser> inside <iframe mozbrowser> correctly.
Bug 844323 - Part 3: ProcessPriorityManager tests.
Bug 844323 - Part 3a: Tests that we handle <iframe mozbrowser> in <iframe mozbrowser> properly with the new, in-process ProcessPriorityManager.
Bug 847592 - Part 1: Add an additional lowCPUPriority argument to hal::SetProcessPriority.
Bug 847592 - Part 2: When a process has priority FOREGROUND_HIGH, renice all other processes.
Bug 847592 - Tests for renicing all other processes when one process gets priority FOREGROUND_HIGH