[Android] Add Java observers to the NetworkChangeNotifier

net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java

Index: net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java
diff --git a/net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java b/net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java
index 911869493e26471773c6f6036cdf8ac1b804526f..c5fd0330f514e08fae45368e1d84414e1bb73d04 100644
--- a/net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java
+++ b/net/android/java/src/org/chromium/net/NetworkChangeNotifierAutoDetect.java
@@ -23,6 +23,31 @@ import org.chromium.base.ActivityStatus;
 public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
         implements ActivityStatus.Listener {
 
+    /** Queries the ConnectivityManager for information about the current connection. */
+    static class ConnectivityManagerDelegate {
+        private ConnectivityManager mConnectivityManager;
+
+        ConnectivityManagerDelegate(Context context) {
+            if (context != null) {
+                mConnectivityManager = (ConnectivityManager)
+                       context.getSystemService(Context.CONNECTIVITY_SERVICE);
+            }
+        }
+
+        boolean activeNetworkExists() {
+            return mConnectivityManager != null &&
+                    mConnectivityManager.getActiveNetworkInfo() != null;
+        }
+
+        int getNetworkType() {
+            return mConnectivityManager.getActiveNetworkInfo().getType();
+        }
+
+        int getNetworkSubtype() {
+            return mConnectivityManager.getActiveNetworkInfo().getSubtype();
+        }
+    }
+
     private static final String TAG = "NetworkChangeNotifierAutoDetect";
 
     private final NetworkConnectivityIntentFilter mIntentFilter =
@@ -31,6 +56,7 @@ public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
     private final Observer mObserver;
 
     private final Context mContext;
+    private ConnectivityManagerDelegate mConnectivityManagerDelegate;
     private boolean mRegistered;
     private int mConnectionType;
 
@@ -44,6 +70,7 @@ public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
     public NetworkChangeNotifierAutoDetect(Observer observer, Context context) {
         mObserver = observer;
         mContext = context;
+        mConnectivityManagerDelegate = new ConnectivityManagerDelegate(context);
         mConnectionType = currentConnectionType(context);
 
         ActivityStatus status = ActivityStatus.getInstance();
@@ -53,6 +80,13 @@ public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
         status.registerListener(this);
     }
 
+    /**
+     * Allows overriding the ConnectivityManagerDelegate for tests.
+     */
+    void setConnectivityManagerDelegateForTests(ConnectivityManagerDelegate delegate) {
+        mConnectivityManagerDelegate = delegate;
+    }
+
     public void destroy() {
         unregisterReceiver();
     }
@@ -79,14 +113,11 @@ public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
 
     private int currentConnectionType(Context context) {
         // Track exactly what type of connection we have.
-        ConnectivityManager connectivityManager = (ConnectivityManager)
-                context.getSystemService(Context.CONNECTIVITY_SERVICE);
-        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
-        if (activeNetworkInfo == null) {
+        if (!mConnectivityManagerDelegate.activeNetworkExists()) {
             return NetworkChangeNotifier.CONNECTION_NONE;
         }
 
-        switch (activeNetworkInfo.getType()) {
+        switch (mConnectivityManagerDelegate.getNetworkType()) {
             case ConnectivityManager.TYPE_ETHERNET:
                 return NetworkChangeNotifier.CONNECTION_ETHERNET;
             case ConnectivityManager.TYPE_WIFI:
@@ -95,7 +126,7 @@ public class NetworkChangeNotifierAutoDetect extends BroadcastReceiver
                 return NetworkChangeNotifier.CONNECTION_4G;
             case ConnectivityManager.TYPE_MOBILE:
                 // Use information from TelephonyManager to classify the connection.
-                switch (activeNetworkInfo.getSubtype()) {
+                switch (mConnectivityManagerDelegate.getNetworkSubtype()) {
                     case TelephonyManager.NETWORK_TYPE_GPRS:
                     case TelephonyManager.NETWORK_TYPE_EDGE:
                     case TelephonyManager.NETWORK_TYPE_CDMA: