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"