Document correct context for obtaining WifiManager

Added comments to both WifiManager WIFI_SERVICE.

Bug: 25015174
Change-Id: Ibd1e21d860ef2b7cc432b3da76671d22c02ef7cb
diff --git a/core/java/android/content/Context.java b/core/java/android/content/Context.java
index 3f18ea9..f908abc 100644
--- a/core/java/android/content/Context.java
+++ b/core/java/android/content/Context.java
@@ -2761,8 +2761,10 @@
      *  <dd> A {@link android.net.ConnectivityManager ConnectivityManager} for
      *  handling management of network connections.
      *  <dt> {@link #WIFI_SERVICE} ("wifi")
-     *  <dd> A {@link android.net.wifi.WifiManager WifiManager} for management of
-     * Wi-Fi connectivity.
+     *  <dd> A {@link android.net.wifi.WifiManager WifiManager} for management of Wi-Fi
+     *  connectivity.  On releases before NYC, it should only be obtained from an application
+     *  context, and not from any other derived context to avoid memory leaks within the calling
+     *  process.
      *  <dt> {@link #WIFI_P2P_SERVICE} ("wifip2p")
      *  <dd> A {@link android.net.wifi.p2p.WifiP2pManager WifiP2pManager} for management of
      * Wi-Fi Direct connectivity.
diff --git a/wifi/java/android/net/wifi/WifiManager.java b/wifi/java/android/net/wifi/WifiManager.java
index bbc3d2f..1633bd9c9 100644
--- a/wifi/java/android/net/wifi/WifiManager.java
+++ b/wifi/java/android/net/wifi/WifiManager.java
@@ -49,6 +49,8 @@
  * This class provides the primary API for managing all aspects of Wi-Fi
  * connectivity. Get an instance of this class by calling
  * {@link android.content.Context#getSystemService(String) Context.getSystemService(Context.WIFI_SERVICE)}.
+ * On releases before NYC, it should only be obtained from an application context, and not from
+ * any other derived context to avoid memory leaks within the calling process.
 
  * It deals with several categories of items:
  * <ul>