bluetooth: Improve GATT disconnected error message.

third_party/WebKit/LayoutTests/bluetooth/script-tests/server/garbage-collection-ran-during-error.js

 'use strict';
 promise_test(() => {
   let promise;
   return setBluetoothFakeAdapter('MissingServiceHeartRateAdapter')
-    .then(() => requestDeviceWithKeyDown({
-      filters: [{services: ['heart_rate']}]}))
-    .then(device => device.gatt.connect())
-    .then(gattServer => {
-      promise = assert_promise_rejects_with_message(
-        gattServer.CALLS([
-          getPrimaryService('heart_rate')|
-          getPrimaryServices()|
-          getPrimaryServices('heart_rate')[UUID]]),
-        new DOMException(
-          'GATT Server disconnected while retrieving services.',
-          'NetworkError'));
-      // Disconnect called to clear attributeInstanceMap and allow the
-      // object to get garbage collected.
-      gattServer.disconnect();
-    })
-    .then(runGarbageCollection)
-    .then(() => promise);
+      .then(
+          () =>
+              requestDeviceWithKeyDown({filters: [{services: ['heart_rate']}]}))
+      .then(device => device.gatt.connect())
+      .then(gattServer => {
+        promise = assert_promise_rejects_with_message(
+            gattServer.CALLS(
+                [getPrimaryService('heart_rate') | getPrimaryServices() |
+                 getPrimaryServices('heart_rate')[UUID]]),
+            new DOMException(
+                'GATT Server is disconnected. ' +
+                    'Cannot retrieve services. ' +
+                    '(Re)connect first with `device.gatt.connect`.',
+                'NetworkError'));
+        // Disconnect called to clear attributeInstanceMap and allow the
+        // object to get garbage collected.
+        gattServer.disconnect();
+      })
+      .then(runGarbageCollection)
+      .then(() => promise);
 }, 'Garbage Collection ran during a FUNCTION_NAME call that failed. ' +
    'Should not crash.');