When we receive build settings after hitting the timeout, we call `fileBuildSettingsChanged` on the delegate, which should cause the document to get re-opened in sourcekitd and diagnostics to get refreshed. rdar://136332685
BuildSystemManager
BuildSystemMessageDependencyTracker
BuildTargetIdentifier
ConfiguredTarget
CompilationDatabase.swift
CompilationDatabaseBuildSystem
FallbackBuildSystem
FileBuildSettings.patching
PrefixMessageWithTaskEmoji.swift
QueueBasedMessageHandler
SKCore
BuildSystemIntegration