* Rename PopupProxyHost to PopupFactory
* Update FrontendApiReceiver to support non-async handlers
* Make some functions non-async
* Make setCustomCss non-async
* Make setContentScale non-async
* Remove static
* Rename variables
* Pass frameId into PopupFactory's constructor
* Change FrontendApiReceiver source from popup-proxy-host to popup-factor
* Rename _invokeHostApi to _invoke
* Rename PopupProxy.getHostUrl to getUrl
* Make Frontend use composition instead of inheritance for TextScanner
* Use push instead of concat
* Update setOptions and setEnabled APIs
* Update how onWindowMessage event listener is added/removed
* Rename options to _options
* Use bind instead of arrow function
* Fix selection being cleared due to settings changes
* Remove _getVisualViewportScale
* Use super's mouse event listener definitions
* Remove redundant override
* Remove getTouchEventListeners override
* Rename Display.onSearchClear to onEscape
* Change onSearchClear to clearSelection and use an event
* Update how text is marked for selection and deselection
* Replace onError with yomichan.logError
* Update setEnabled to refresh all event listeners
* set optionsContext from Frontend
* update Popup+Display options on Frontend change
* remove popup setOptions
* only update DisplayFloat options from Frontend
* fix optionsContext usage
* fix preview frame arguments
* keep Frontend URL up to date
* cache url
* fix preview frame
* trigger modifyingProfileChange in correct places
* remove async from function not using await
* refactor optionsContext in Frontend
