Issue 4223 - Migrate some more of adblockplustests

test/stub-modules/io.js

-exports.IO = {};
+//
+// Fake nsIFile implementation for our I/O
+//
+function FakeFile(path)
+{
+  this.path = path;
+}
+FakeFile.prototype =
+{
+  get leafName()
+  {
+    return this.path;
+  },
+  set leafName(value)
+  {
+    this.path = value;
+  },
+  append: function(path)
+  {
+    this.path += path;
+  },
+  clone: function()
+  {
+    return new FakeFile(this.path);
+  },
+  get parent()
+  {
+    return {create: function() {}};
+  },
+  normalize: function() {}
+};
+
+
+exports.IO = {
+  resolveFilePath: function(path)
+  {
+    return new FakeFile(path);
+  },
+  statFile: function(path)
+  {
+    return true;
+  }
+};