Hard crash when changing accessibility settings

I could not reproduce this on a simple starter project, so this must be due to something I am doing in my application code but I have no idea where to look. I'm hoping someone could point me down the right path to resolving this.

Essentially, on Android when I toggle the "Large Text" accessibility option on or off and then return to my app, it crashes. My app is idle at the time, with no running animations (although animations might have been used at some point prior in the app lifetime). I mention that detail because the error seems to implicate something related to animations.

If I restart the app then it works fine (although ugly) with the new setting in effect.

The error I get is:

System.ArgumentException: 'jobject' must not be IntPtr.Zero.
Parameter name: jobject
at Android.Runtime.JNIEnv.CallVoidMethod (intptr,intptr) [0x00010] in /Users/builder/data/lanes/2058/58099c53/source/monodroid/src/Mono.Android/src/Runtime/JNIEnv.g.cs:546
at Android.Animation.Animator.Cancel () [0x00043] in /Users/builder/data/lanes/2058/58099c53/source/monodroid/src/Mono.Android/platforms/android-22/src/generated/Android.Animation.Animator.cs:839
at Xamarin.Forms.Platform.Android.AndroidTicker.DisableTimer () <IL 0x00006, 0x0002a>
at Xamarin.Forms.Ticker.Disable () <IL 0x0000c, 0x00044>
at Xamarin.Forms.Ticker.SendSignals (int) <IL 0x000ac, 0x003e3>
at Xamarin.Forms.Platform.Android.AndroidTicker.<.ctor>b__1_0 (object,Android.Animation.ValueAnimator/AnimatorUpdateEventArgs) <IL 0x00002, 0x0002f>
at Android.Animation.ValueAnimator/IAnimatorUpdateListenerImplementor.OnAnimationUpdate (Android.Animation.ValueAnimator) [0x0000d] in /Users/builder/data/lanes/2058/58099c53/source/monodroid/src/Mono.Android/platforms/android-22/src/generated/Android.Animation.ValueAnimator.cs:136
at Android.Animation.ValueAnimator/IAnimatorUpdateListenerInvoker.n_OnAnimationUpdate_Landroid_animation_ValueAnimator_ (intptr,intptr,intptr) [0x00011] in /Users/builder/data/lanes/2058/58099c53/source/monodroid/src/Mono.Android/platforms/android-22/src/generated/Android.Animation.ValueAnimator.cs:85
at (wrapper dynamic-method) object.231480df-1ead-480f-8baa-2a1da7fc4fcb (intptr,intptr,intptr) <IL 0x00017, 0x00027>