Method 'ProgressBar.set_IndeterminateTintList' not found.

I'm trying to upgrade a Xamarin Forms app to the latest 1.4.3.6376 and I'm getting the following error. I think it's happening on the ActivityIndicator but not certain. I've updated the Target Android Version to API level 21 as suggested in other threads and still get the error. Any ideas?

Java.Lang.RuntimeException: java.lang.reflect.InvocationTargetException
  at --- End of managed exception stack trace ---
  at java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
  at at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
  at at dalvik.system.NativeStart.main(Native Method)
  at Caused by: java.lang.reflect.InvocationTargetException
  at at java.lang.reflect.Method.invokeNative(Native Method)
  at at java.lang.reflect.Method.invoke(Method.java:515)
  at at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
  at ... 2 more
  at Caused by: md52ce486a14f4bcd95899665e9d932190b.JavaProxyThrowable: System.MissingMethodException: Method 'ProgressBar.set_IndeterminateTintList' not found.
  at at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () <IL 0x00011, 0x0004b>
  at at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<ThrowAsync>m__0 (object) <IL 0x00006, 0x0003b>
  at at Android.App.SyncContext/<Post>c__AnonStorey0.<>m__0 () <IL 0x0000c, 0x00032>
  at at Java.Lang.Thread/RunnableImplementor.Run () <IL 0x00011, 0x0004c>
  at at Java.Lang.IRunnableInvoker.n_Run (intptr,intptr) <IL 0x0000a, 0x0005e>
  at at (wrapper dynamic-method) object.030d311b-89b7-406d-bcdf-9a891c283b53 (intptr,intptr) <IL 0x00011, 0x0001f>
  at at mono.java.lang.RunnableImplementor.n_run(Native Method)
  at at mono.java.lang.RunnableImplementor.run(RunnableImplementor.java:29)
  at at android.os.Handler.handleCallback(Handler.java:733)
  at at android.os.Handler.dispatchMessage(Handler.java:95)
  at at android.os.Looper.loop(Looper.java:136)
  at at android.app.ActivityThread.main(ActivityThread.java:5017)
  at ... 5 more