FeedItemType:
| "TrackedChange"
| "UserStatus"
| "TextPost"
| "AdvancedTextPost"
| "LinkPost"
| "ContentPost"
| "PollPost"
| "RypplePost"
| "ProfileSkillPost"
| "DashboardComponentSnapshot"
| "ApprovalPost"
| "CaseCommentPost"
| "ReplyPost"
| "EmailMessageEvent"
| "CallLogPost"
| "ChangeStatusPost"
| "AttachArticleEvent"
| "MilestoneEvent"
| "ActivityEvent"
| "ChatTranscriptPost"
| "CollaborationGroupCreated"
| "CollaborationGroupUnarchived"
| "SocialPost"
| "QuestionPost"
| "FacebookPost"
| "BasicTemplateFeedItem"
| "CreateRecordEvent"
| "CanvasPost"
| "AnnouncementPost"