Use chrome.storage to sync data

[midenok]

https://developer.chrome.com/extensions/storage

As per QUOTA_BYTES of chrome.storage.sync max data size is 100 KiB. That should be enough to store all styles data (possibly compressed) for most user needs. If there is not enough room, user should choose which styles to not sync.

Links

• https://developer.chrome.com/extensions/storage

[midenok]

Currently data is stored in WebSQL (storage-websql.js, storage.js)

https://www.w3.org/TR/webdatabase/

function saveStyle(o, callback) {
	getDatabase(function(db) {
		var tx = db.transaction(["styles"], "readwrite");
		var os = tx.objectStore("styles");

		// Update
		if (o.id) {
			var request = os.get(Number(o.id));
			request.onsuccess = function(event) {
				var style = request.result || {};
				for (var prop in o) {
					if (prop == "id") {
						continue;
					}
					style[prop] = o[prop];
				}
				request = os.put(style);
				request.onsuccess = function(event) {
					notifyAllTabs({method: "styleUpdated", style: style});
					invalidateCache(true);
					if (callback) {
						callback(style);
					}
				};
			};
			return;
		}

The best way maybe is to imitate API (getDatabase, db, tx, os) for chrome.storage in storage-chrome.js.

TODO: look how it works in latest plugin version.