Fully migrate to ICU

ts/types/Attachment.ts

@@ -849,9 +849,9 @@ export function getAlt(
   i18n: LocalizerType
 ): string {
   if (isVideoAttachment(attachment)) {
-    return i18n('videoAttachmentAlt');
+    return i18n('icu:videoAttachmentAlt');
   }
-  return i18n('imageAttachmentAlt');
+  return i18n('icu:imageAttachmentAlt');
 }
 
 // Migration-related attachment stuff

ts/types/Stories.ts

@@ -146,7 +146,7 @@ export function getStoryDistributionListName(
   id: string,
   name: string
 ): string {
-  return id === MY_STORY_ID ? i18n('Stories__mine') : name;
+  return id === MY_STORY_ID ? i18n('icu:Stories__mine') : name;
 }
 
 export enum HasStories {