first attempt of implementation of new method
WIP; second attempt of implementation of new method - without group by in SQL query
WIP; second attempt of implementation of new method; array() => []
WIP; added failing unit test
fixed failing unit test
WIP; one more use case in unit test
refactoring: removed RevisionService::getRecentlyChangedArticles(), renamed RevisionService::filterByPageId() to RevisionService::filterByArticle()
refactoring: removed duplicated code from ActivityApiController, renamed $duplicatesFilter to $duplicatesFilterMethod
added description of new method to documentation file
removed unused variable from use() statement
renamed variable
CR changes: used hash lookup instead of array lookup
Merge pull request #3755 from Wikia/MOB-1141

MOB-1141 New method in Latest Activity Api (P2 fix)