Don't re-hide the keyguard if it isn't showing.

This has a horrifying and unpredictable side effect of triggering
post-unlock Runnables that are stored in StatusBar.java, which can
result in a blank screen on unlock in certain race conditions.

Test: unlock, launch an app during the unlock animation, press power, wake up at bad time
Test: I wrote a custom build to force the above scenario to verify this works
Fixes: 214647311
Merged-In: I00655c2e85c46bd0c52b77094757e155b1a6f9c9
Change-Id: I9261ab9f04cc06db379676dccca72e452ece98d7

packages/SystemUI/src/com/android/systemui/keyguard/KeyguardUnlockAnimationController.kt

@@ -21,6 +21,7 @@ import android.animation.AnimatorListenerAdapter
 import android.animation.ValueAnimator
 import android.content.Context
 import android.graphics.Matrix
+import android.util.Log
 import android.view.RemoteAnimationTarget
 import android.view.SyncRtSurfaceTransactionApplier
 import android.view.View
@@ -38,6 +39,8 @@ import com.android.systemui.statusbar.policy.KeyguardStateController
 import dagger.Lazy
 import javax.inject.Inject
 
+const val TAG = "KeyguardUnlock"
+
 /**
  * Starting scale factor for the app/launcher surface behind the keyguard, when it's animating
  * in during keyguard exit.
@@ -254,7 +257,12 @@ class KeyguardUnlockAnimationController @Inject constructor(
     }
 
     fun hideKeyguardViewAfterRemoteAnimation() {
-        keyguardViewController.hide(surfaceBehindRemoteAnimationStartTime, 350)
+        if (keyguardViewController.isShowing) {
+            keyguardViewController.hide(surfaceBehindRemoteAnimationStartTime, 350)
+        } else {
+            Log.e(TAG, "#hideKeyguardViewAfterRemoteAnimation called when keyguard view is not " +
+                    "showing. Ignoring...")
+        }
     }
 
     /**