Earlgrey Test is hanging on Xcode 9

When running Earlgrey test with my app being the target on xcode 9, the test hung after inputing some number with keyboard or replacing text in a popup dialog. I already updated Earlgrey to v1.12.1. The following is the log:
Test hung after inputing with keyboard:

[log_earlgrey.txt](https://github.com/google/EarlGrey/files/1387046/log_earlgrey.txt)

Test hung after replacing text in a popup dialog:

> Full state transition call stack for all objects:
=> Waiting for viewDidAppear: call on the view controller. Please ensure that this view controller and its subclasses call through to their super's implementation.
Waiting for window's rootViewController to appear. This should happen in the next runloop drain after a window's state is changed to visible.
(
0 EarlGrey 0x000000010afd544d -[GREYAppStateTrackerObject setState:] + 61,
1 EarlGrey 0x000000010afd3e55 __133-[GREYAppStateTracker grey_changeState:usingOperation:forObject:orInternalObjectDeallocationTracker:orExternalAppStateTrackerObject:]_block_invoke + 1157,
2 EarlGrey 0x000000010afd3020 -[GREYAppStateTracker grey_performBlockInCriticalSection:] + 336,
3 EarlGrey 0x000000010afd3882 -[GREYAppStateTracker grey_changeState:usingOperation:forObject:orInternalObjectDeallocationTracker:orExternalAppStateTrackerObject:] + 1378,
4 EarlGrey 0x000000010afd17ff -[GREYAppStateTracker trackState:forObject:] + 95,
5 EarlGrey 0x000000010af7ea6e -[UIViewController(GREYAdditions) grey_trackAsRootViewControllerForWindow:] + 462,
6 EarlGrey 0x000000010af810d0 -[UIWindow(GREYAdditions) greyswizzled_setHidden:] + 128,
7 UIKit 0x000000010c2be7b9 -[UIWindow orderFront:] + 24,
8 UIKit 0x000000010c722ca9 -[UITextEffectsWindow didA, ,