Revert "Bug 40090: Disable v3 add-on blocklist for now"

This reverts commit ee9af308.

browser/app/profile/firefox.js

@@ -42,9 +42,9 @@ pref("extensions.getAddons.link.url", "https://addons.mozilla.org/%LOCALE%/firef
 pref("extensions.getAddons.langpacks.url", "https://services.addons.mozilla.org/api/v3/addons/language-tools/?app=firefox&type=language&appversion=%VERSION%");
 pref("extensions.getAddons.discovery.api_url", "https://services.addons.mozilla.org/api/v4/discovery/?lang=%LOCALE%&edition=%DISTRIBUTION%");
 
-// No bloomfilters for the addons blocklist for now, but JSON only.
-pref("extensions.blocklist.useMLBF", false);
-pref("extensions.blocklist.useMLBF.stashes", false);
+// Use bloomfilters for the addons blocklist, instead of JSON only.
+pref("extensions.blocklist.useMLBF", true);
+pref("extensions.blocklist.useMLBF.stashes", true);
 
 // The URL for the privacy policy related to recommended extensions.
 pref("extensions.recommendations.privacyPolicyUrl", "https://www.mozilla.org/privacy/firefox/?utm_source=firefox-browser&utm_medium=firefox-browser&utm_content=privacy-policy-link#addons");