Bug 1245277 pocket addon needs to respect prior set default prefs, r=Gijs

browser/extensions/pocket/bootstrap.js

@@ -41,6 +41,10 @@ const PREFS = {
 function setDefaultPrefs() {
   let branch = Services.prefs.getDefaultBranch(PREF_BRANCH);
   for (let [key, val] in Iterator(PREFS)) {
+    // If someone beat us to setting a default, don't overwrite it.  This can
+    // happen if distribution.ini sets the default first.
+    if (branch.getPrefType(key) != branch.PREF_INVALID)
+      continue;
     switch (typeof val) {
       case "boolean":
         branch.setBoolPref(key, val);
@@ -519,8 +523,7 @@ function startup(data, reason) {
     }
     // watch pref change and enable/disable if necessary
     Services.prefs.addObserver("extensions.pocket.enabled", prefObserver, false);
-    if (Services.prefs.prefHasUserValue("extensions.pocket.enabled") &&
-        !Services.prefs.getBoolPref("extensions.pocket.enabled"))
+    if (!Services.prefs.getBoolPref("extensions.pocket.enabled"))
       return;
     PocketOverlay.startup(reason);
   });