Previously we incorrectly assumed that each sub-element is present in addedNodes array, but actually we need to inspect each added node's children e.g. using the superfast getElementsByTagName.
Popup:
* Enforce 200-800px range for the popup width option
Manage:
* faster search via cachedStyles.byId
* faster restoration of search results on history nav
* style name is clickable and opens the editor
* animated highlight of style element on update/add/save
* expandable extra applies-to targets
* remember scroll position on normal history navigation
* boz-sizing in #header, also in editor
* applies-to targets use structured markup
* get*Tab*, enableStyle and deleteStyle are promisified
Previously, when a cache was invalidated and every tab/iframe issued a getStyles request, we previous needlessly accessed IndexedDB for each of these requests. It happened because 1) the global cachedStyles was created only at the end of the async DB-reading, 2) and each style record is retrieved asynchronously so the single threaded JS engine interleaved all these operations. It could easily span a few seconds when many tabs are open and you have like 100 styles.
Now, in getStyles: all requests issued while cachedStyles is being populated are queued and invoked at the end.
Now, in filterStyles: all requests are cached using the request's options combined in a string as a key. It also helps on each navigation because we monitor page loading process at different stages: before, when committed, history traversal, requesting applicable styles by a content script. Icon badge update also may issue a copy of the just issued request by one of the navigation listeners.
Now, the caches are invalidated smartly: style add/update/delete/toggle only purges filtering cache, and modifies style cache in-place without re-reading the entire IndexedDB.
Now, code:false mode for manage page that only needs style meta. It reduces the transferred message size 10-100 times thus reducing the overhead caused by to internal JSON-fication in the extensions API.
Also fast&direct getStylesSafe for own pages; code cosmetics
