Issue 4023 - Use localforage (IndexedDB) instead of localStorage

lib/adblockplus.js

Index: lib/adblockplus.js
===================================================================
--- a/lib/adblockplus.js
+++ b/lib/adblockplus.js
@@ -365,52 +365,33 @@
       ext.storage.get([key], function(items)
       {
         var entry = items[key];
-        if (!entry)
-        {
-          try
+        if (entry)
+        {
+          resolve(entry);
+        }
+        else
+        {
+          entry = localforage.getItem(key, function(err, value) 
           {
-            entry = JSON.parse(window.localStorage.getItem(key));
-          }
-          catch (err)
-          {}
-        }
-        if (entry)
-        {
-          resolve(entry);
-        }
-        else
-        {
-          reject(new Error("File doesn't exist"));
+            if (err || !value)
+              reject(new Error("File doesn't exist"));                
+            else
+              resolve(value);
+          });
         }
       });
     }.bind(this));
   }
   function saveFile(file, data, callback)
   {
-    var entry = {};
     var key = fileToKey(file);
+    var entry = {
+      lastModified: Date.now(),
+      content: data
+    };
 
-    if (typeof browser == "undefined")
-    {
-      entry[key] = {
-        lastModified: Date.now(),
-        content: data
-      };
-      ext.storage.set(entry, callback);
-    }
-    else
-    {
-      var processedData = LZString.compressToUTF16(JSON.stringify(data));
-      ext.storage.remove(key);
-      entry[key] = {
-        lastModified: Date.now(),
-        content: processedData,
-        compressed: true
-      };
-      window.localStorage.setItem(key, JSON.stringify(entry[key]));
-      setTimeout(callback, 0);
-    }
-    callback();
+    ext.storage.remove(key);
+    localforage.setItem(key, entry, callback);
   }
   exports.IO = {
     resolveFilePath: function(path)
@@ -423,10 +404,6 @@
       {
         if ("content" in entry)
         {
-          if (entry["compressed"])
-          {
-            entry.content = JSON.parse(LZString.decompressFromUTF16(entry.content));
-          }
           for (var _loopIndex15 = 0; _loopIndex15 < entry.content.length; ++_loopIndex15)
           {
             var line = entry.content[_loopIndex15];