From da23618043667e9cee680688b7413f65b400516e Mon Sep 17 00:00:00 2001
From: Robin Lee <rgl@google.com>
Date: Fri, 12 Aug 2016 12:46:28 +0100
Subject: [PATCH] Documentation warning against short-lived Contexts

It's better to use an Application Context rather than hoping the
activity won't be destroyed in another thread (because it will).

Change-Id: I9bf842d0d7dbedcc509a4a314d23a9a6cfca4d48
Fix: 29873669
---
 keystore/java/android/security/KeyChain.java | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/keystore/java/android/security/KeyChain.java b/keystore/java/android/security/KeyChain.java
index cce58c2096f35..be9ebb58675ef 100644
--- a/keystore/java/android/security/KeyChain.java
+++ b/keystore/java/android/security/KeyChain.java
@@ -20,6 +20,7 @@ import android.annotation.Nullable;
 import android.annotation.WorkerThread;
 import android.app.Activity;
 import android.app.PendingIntent;
+import android.app.Service;
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
@@ -356,6 +357,9 @@ public final class KeyChain {
      *
      * <p> This method may block while waiting for a connection to another process, and must never
      * be called from the main thread.
+     * <p> As {@link Activity} and {@link Service} contexts are short-lived and can be destroyed
+     * at any time from the main thread, it is safer to rely on a long-lived context such as one
+     * returned from {@link Context#getApplicationContext()}.
      *
      * @param alias The alias of the desired private key, typically returned via
      *              {@link KeyChainAliasCallback#alias}.
@@ -400,6 +404,9 @@ public final class KeyChain {
      *
      * <p> This method may block while waiting for a connection to another process, and must never
      * be called from the main thread.
+     * <p> As {@link Activity} and {@link Service} contexts are short-lived and can be destroyed
+     * at any time from the main thread, it is safer to rely on a long-lived context such as one
+     * returned from {@link Context#getApplicationContext()}.
      *
      * @param alias The alias of the desired certificate chain, typically
      * returned via {@link KeyChainAliasCallback#alias}.