Revert r8183; broke unit tests as these functions can be called after headers are sent (which needs further investigation in a separate ticket.)

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8185 cdf35c40-ae34-48e0-9cc9-0c9da1808c22
Pass additional data along to bp_core_signup_send_activation_key filter

See #5481

Props StijnDeWitt

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8186 cdf35c40-ae34-48e0-9cc9-0c9da1808c22
Add 'bp_activity_paged_activities_sql' filter, to allow last-minute filtering of activity IDs SQL query

Fixes #5480

git-svn-id: https://buddypress.svn.wordpress.org/trunk@8187 cdf35c40-ae34-48e0-9cc9-0c9da1808c22