Singletons changes necessary to run the UI Service inside the browser's process.

ui/events/devices/input_device_manager.h

Index: ui/events/devices/input_device_manager.h
diff --git a/ui/events/devices/input_device_manager.h b/ui/events/devices/input_device_manager.h
index 83835ad854ab3c20ffb0181eff417bad135c8115..59526ea357de5571ea321902c2a9669dcca41283 100644
--- a/ui/events/devices/input_device_manager.h
+++ b/ui/events/devices/input_device_manager.h
@@ -15,8 +15,8 @@
 
 namespace ui {
 
-// Interface to query available input devices. Holds a static pointer to an
-// implementation that provides this service. The implementation could be
+// Interface to query available input devices. Holds a thread-local pointer to
+// an implementation that provides this service. The implementation could be
 // DeviceDataManager or something that mirrors the necessary state if
 // DeviceDataManager is in a different process.
 class EVENTS_DEVICES_EXPORT InputDeviceManager {
@@ -39,7 +39,7 @@ class EVENTS_DEVICES_EXPORT InputDeviceManager {
   virtual void RemoveObserver(InputDeviceEventObserver* observer) = 0;
 
  protected:
-  // Sets the instance. This should only be set once per process.
+  // Sets the instance. This should only be set once per thread.
   static void SetInstance(InputDeviceManager* instance);
 
   // Clears the instance. InputDeviceManager doesn't own the instance and won't