Use javascript 1.7 to use 'yield' for PlacesBackups.getBookmarksTree()
Use javascript 1.7 to use 'yield' for PlacesBackups.getBookmarksTree()

PlacesUtils.serializeNodeAsJSONToOutputStream() was deprecated.
It can be replaced by PlacesBackups.getBookmarksTree(), but it requires
the asynchronous processing.

This introduces javascript 1.7 so that bkviewer.js can process the result of
getBookmarksTree() like BookmarkJSONUtils.exportToFile().

alprut/bkviewer