diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 7e230a3..369968f 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -301,6 +301,19 @@
     public static final int START_INTENT_NOT_RESOLVED = FIRST_START_FATAL_ERROR_CODE + 9;
 
     /**
+     * Result for IActivityManager.startAssistantActivity: active session is currently hidden.
+     * @hide
+     */
+    public static final int START_ASSISTANT_HIDDEN_SESSION = FIRST_START_FATAL_ERROR_CODE + 10;
+
+    /**
+     * Result for IActivityManager.startAssistantActivity: active session does not match
+     * the requesting token.
+     * @hide
+     */
+    public static final int START_ASSISTANT_NOT_ACTIVE_SESSION = FIRST_START_FATAL_ERROR_CODE + 11;
+
+    /**
      * Result for IActivityManaqer.startActivity: the activity was started
      * successfully as normal.
      * @hide
diff --git a/core/java/android/app/Instrumentation.java b/core/java/android/app/Instrumentation.java
index 16cbb7c..dbea349 100644
--- a/core/java/android/app/Instrumentation.java
+++ b/core/java/android/app/Instrumentation.java
@@ -1953,6 +1953,12 @@
             case ActivityManager.START_VOICE_HIDDEN_SESSION:
                 throw new IllegalStateException(
                         "Cannot start voice activity on a hidden session");
+            case ActivityManager.START_ASSISTANT_NOT_ACTIVE_SESSION:
+                throw new IllegalStateException(
+                        "Session calling startAssistantActivity does not match active session");
+            case ActivityManager.START_ASSISTANT_HIDDEN_SESSION:
+                throw new IllegalStateException(
+                        "Cannot start assistant activity on a hidden session");
             case ActivityManager.START_CANCELED:
                 throw new AndroidRuntimeException("Activity could not be started for "
                         + intent);
diff --git a/core/java/android/service/voice/VoiceInteractionSession.java b/core/java/android/service/voice/VoiceInteractionSession.java
index a2a129d..625dd9e 100644
--- a/core/java/android/service/voice/VoiceInteractionSession.java
+++ b/core/java/android/service/voice/VoiceInteractionSession.java
@@ -235,6 +235,8 @@
 
         @Override
         public void hide() {
+            // Remove any pending messages to show the session
+            mHandlerCaller.removeMessages(MSG_SHOW);
             mHandlerCaller.sendMessage(mHandlerCaller.obtainMessage(MSG_HIDE));
         }
 
diff --git a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerServiceImpl.java b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerServiceImpl.java
index 0c5e4bd..3788cf33 100644
--- a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerServiceImpl.java
+++ b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionManagerServiceImpl.java
@@ -16,6 +16,8 @@
 
 package com.android.server.voiceinteraction;
 
+import static android.app.ActivityManager.START_ASSISTANT_HIDDEN_SESSION;
+import static android.app.ActivityManager.START_ASSISTANT_NOT_ACTIVE_SESSION;
 import static android.app.ActivityManager.START_VOICE_HIDDEN_SESSION;
 import static android.app.ActivityManager.START_VOICE_NOT_ACTIVE_SESSION;
 
@@ -212,11 +214,11 @@
         try {
             if (mActiveSession == null || token != mActiveSession.mToken) {
                 Slog.w(TAG, "startAssistantActivity does not match active session");
-                return START_VOICE_NOT_ACTIVE_SESSION;
+                return START_ASSISTANT_NOT_ACTIVE_SESSION;
             }
             if (!mActiveSession.mShown) {
                 Slog.w(TAG, "startAssistantActivity not allowed on hidden session");
-                return START_VOICE_HIDDEN_SESSION;
+                return START_ASSISTANT_HIDDEN_SESSION;
             }
             intent = new Intent(intent);
             intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
diff --git a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionSessionConnection.java b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionSessionConnection.java
index 4267ec4..d394d63 100644
--- a/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionSessionConnection.java
+++ b/services/voiceinteraction/java/com/android/server/voiceinteraction/VoiceInteractionSessionConnection.java
@@ -453,6 +453,7 @@
                 mShowFlags = 0;
                 mHaveAssistData = false;
                 mAssistData.clear();
+                mPendingShowCallbacks.clear();
                 if (mSession != null) {
                     try {
                         mSession.hide();