In the current system (as of Mustang-B89), if the can_generate_all_class_hook_events
capability is acquired in the OnLoad phase, then sharing is disabled. If sharing is
not enabled then the can_generate_all_class_hook_events capability can be acquired
in any phase. If sharing is enabled, then the can_generate_all_class_hook_events
capability cannot be acquired after the OnLoad phase.

During discussions about 5002268, 6431456 and 4956521, changing the relationship
between can_generate_all_class_hook_events and sharing was also discussed. A couple
of possibilities emerged:

1) If can_generate_all_class_hook_events is acquired in the OnLoad phase,
   then don't disable sharing. Instead remap the shared readonly space to
   shared readwrite, private (see 5002268) and post CFLH events for all
   shared classes.

2) Keep the logic that disables sharing if can_generate_all_class_hook_events
   is acquired in the OnLoad phase. Allow can_generate_all_class_hook_events
   to be acquired in any phase. If can_generate_all_class_hook_events is
   acquired after the OnLoad phase, then CFLH events don't need to be posted
   for the shared classes in any case since the classes were "loaded" before
   the capability was acquired.

Option 2 is much simpler so that option is looking best at the moment.