Drop unneeded binds

There are no references to `this` in these functions.

// FREEBIE

libtextsecure/account_manager.js

@@ -34,8 +34,8 @@
                         then(generateKeys).
                         then(registerKeys).
                         then(registrationDone);
-                }.bind(this));
-            }.bind(this));
+                });
+            });
         },
         registerSecondDevice: function(setProvisioningUrl, confirmNumber, progressCallback) {
             var createAccount = this.createAccount.bind(this);
@@ -106,7 +106,7 @@
                     if (preKeyCount < 10) {
                         return generateKeys().then(registerKeys);
                     }
-                }.bind(this));
+                });
             }.bind(this));
         },
         rotateSignedPreKey: function() {