diff --git a/core/java/android/app/ActivityTransitionState.java b/core/java/android/app/ActivityTransitionState.java
index 4a1aff74ddf64..02eb4d3ded1c1 100644
--- a/core/java/android/app/ActivityTransitionState.java
+++ b/core/java/android/app/ActivityTransitionState.java
@@ -284,7 +284,7 @@ class ActivityTransitionState {
     }
 
     public boolean startExitBackTransition(final Activity activity) {
-        if (mEnteringNames == null) {
+        if (mEnteringNames == null || mCalledExitCoordinator != null) {
             return false;
         } else {
             if (!mHasExited) {
diff --git a/core/java/android/app/EnterTransitionCoordinator.java b/core/java/android/app/EnterTransitionCoordinator.java
index a5995846014e5..8bf1e9a97e484 100644
--- a/core/java/android/app/EnterTransitionCoordinator.java
+++ b/core/java/android/app/EnterTransitionCoordinator.java
@@ -150,6 +150,7 @@ class EnterTransitionCoordinator extends ActivityTransitionCoordinator {
                 }
             };
             decor.getViewTreeObserver().addOnPreDrawListener(mViewsReadyListener);
+            decor.invalidate();
         }
     }