title: A console full of <FIRInstanceID/WARNING> - Xcode 8 / iOS10
body: <p>I am having issues with Firebase within Xcode 8 / iOS 10 / Swift 3.
  Trying to just get Firebase Analytics all set up. However in iOS10, the console gets logged with a plethora of WARNING logs from Firebase. These do not happen when I run iOS 9.3 in the simulator. I took the exact steps as noted here: <a href="https://firebase.google.com/docs/analytics/ios/start" rel="noreferrer">https://firebase.google.com/docs/analytics/ios/start</a> </p>
  
  <p>Here is what the log looks like:</p>
  
  <pre><code>&lt;FIRAnalytics/INFO&gt; Firebase Analytics v.3402000 started
  &lt;FIRAnalytics/INFO&gt; To enable debug logging set the following application argument: -FIRAnalyticsDebugEnabled
  &lt;FIRAnalytics/INFO&gt; Successfully created Firebase Analytics App Delegate Proxy automatically. To disable the proxy, set the flag FirebaseAppDelegateProxyEnabled to NO in the Info.plist
  &lt;FIRInstanceID/WARNING&gt; Failed to remove checkin auth credentials from Keychain Error Domain=com.google.iid Code=-34018 "(null)"
  &lt;FIRInstanceID/WARNING&gt; Error failed to remove all tokens from keychain Error Domain=com.google.iid Code=-34018 "(null)"
  &lt;FIRInstanceID/WARNING&gt; FIRInstanceID AppDelegate proxy enabled, will swizzle app delegate remote notification handlers. To disable add "FirebaseAppDelegateProxyEnabled" to your Info.plist and set it to NO
  &lt;FIRInstanceID/WARNING&gt; STOP!! Will reset deviceID from memory.
  &lt;FIRInstanceID/WARNING&gt; Failed to fetch default token Error Domain=com.firebase.iid Code=6 "(null)"
  &lt;FIRInstanceID/WARNING&gt; STOP!! Will reset deviceID from memory.
  &lt;FIRInstanceID/WARNING&gt; Error removing keypair status: -34018
  &lt;FIRInstanceID/WARNING&gt; Unable to remove RSA keypair
  &lt;FIRInstanceID/WARNING&gt; Unable to generate keypair.
  &lt;FIRAnalytics/WARNING&gt; Failed to get InstanceID: Error Domain=com.firebase.iid Code=-34018 "(null)"
  &lt;FIRInstanceID/WARNING&gt; Failed to fetch default token Error Domain=com.firebase.iid Code=501 "(null)" UserInfo={msg=Missing device credentials. Retry later.}
  &lt;FIRInstanceID/WARNING&gt; Failed to retrieve the default GCM token after 5 retries
  </code></pre>
  
  <p>I also get the following error that pops up about every ~30 seconds (while the errors above all don't repeat):</p>
  
  <pre><code>&lt;FIRInstanceID/WARNING&gt; STOP!! Will reset deviceID from memory.
  </code></pre>
  
  <p>Before posting this, I did research and found that the WARNING logs can go away if you enable Keychain Sharing within Capabilities. I am weary of this, however, because no other documentation or explanation was given. And I don't know if that's just masking the errors, or if it's a safe solution here.</p>
  
  <p>Please advise on the safest way to remedy all these WARNING logs.
  Thanks</p>