Remove captive portal code that has no effect.

Note that this CL does not change any behaviour.

At the center of this change is
CaptivePortalTracker#detectCaptivePortal(), which does nothing
except call back into ConnectivityService. Removing it allows us to
simplify code in ConnectivityService. It also allows us to remove
ConnectivityService#captivePortalCheckComplete which was only ever
called in response to this method.

While this does not change any behaviour, it preserves existing
bad behaviour, i.e, that the CAPTIVE_PORTAL_CHECK NetworkInfo
state does not correspond to actual captive portal detection.
We transition into that state and immediately (and unconditionally)
out of it and into CONNECTED.

Change-Id: Ib3797f956d2db5e3cacaaa53e899d81aa8e958af

core/java/android/net/ConnectivityManager.java

@@ -1328,24 +1328,6 @@ public class ConnectivityManager {
         }
     }
 
-    /**
-     * Signal that the captive portal check on the indicated network
-     * is complete and we can turn the network on for general use.
-     *
-     * @param info the {@link NetworkInfo} object for the networkType
-     *        in question.
-     *
-     * <p>This method requires the call to hold the permission
-     * {@link android.Manifest.permission#CONNECTIVITY_INTERNAL}.
-     * {@hide}
-     */
-    public void captivePortalCheckComplete(NetworkInfo info) {
-        try {
-            mService.captivePortalCheckComplete(info);
-        } catch (RemoteException e) {
-        }
-    }
-
     /**
      * Signal that the captive portal check on the indicated network
      * is complete and whether its a captive portal or not.

core/java/android/net/IConnectivityManager.aidl

@@ -129,8 +129,6 @@ interface IConnectivityManager
 
     boolean updateLockdownVpn();
 
-    void captivePortalCheckComplete(in NetworkInfo info);
-
     void captivePortalCheckCompleted(in NetworkInfo info, boolean isCaptivePortal);
 
     void supplyMessenger(int networkType, in Messenger messenger);

services/java/com/android/server/ConnectivityService.java

@@ -2316,36 +2316,6 @@ public class ConnectivityService extends IConnectivityManager.Stub {
         }
     }
 
-    private void handleCaptivePortalTrackerCheck(NetworkInfo info) {
-        if (DBG) log("Captive portal check " + info);
-        int type = info.getType();
-        final NetworkStateTracker thisNet = mNetTrackers[type];
-        if (mNetConfigs[type].isDefault()) {
-            if (mActiveDefaultNetwork != -1 && mActiveDefaultNetwork != type) {
-                if (isNewNetTypePreferredOverCurrentNetType(type)) {
-                    if (DBG) log("Captive check on " + info.getTypeName());
-                    mCaptivePortalTracker.detectCaptivePortal(new NetworkInfo(info));
-                    return;
-                } else {
-                    if (DBG) log("Tear down low priority net " + info.getTypeName());
-                    teardown(thisNet);
-                    return;
-                }
-            }
-        }
-
-        if (DBG) log("handleCaptivePortalTrackerCheck: call captivePortalCheckComplete ni=" + info);
-        thisNet.captivePortalCheckComplete();
-    }
-
-    /** @hide */
-    @Override
-    public void captivePortalCheckComplete(NetworkInfo info) {
-        enforceConnectivityInternalPermission();
-        if (DBG) log("captivePortalCheckComplete: ni=" + info);
-        mNetTrackers[info.getType()].captivePortalCheckComplete();
-    }
-
     /** @hide */
     @Override
     public void captivePortalCheckCompleted(NetworkInfo info, boolean isCaptivePortal) {
@@ -2972,9 +2942,6 @@ public class ConnectivityService extends IConnectivityManager.Stub {
                     if (info.getDetailedState() ==
                             NetworkInfo.DetailedState.FAILED) {
                         handleConnectionFailure(info);
-                    } else if (info.getDetailedState() ==
-                            DetailedState.CAPTIVE_PORTAL_CHECK) {
-                        handleCaptivePortalTrackerCheck(info);
                     } else if (info.isConnectedToProvisioningNetwork()) {
                         /**
                          * TODO: Create ConnectivityManager.TYPE_MOBILE_PROVISIONING