Bug 1191064 - Part 3: Handle removing Android Accounts from fxa-content-server. r=markh

This adds a new JS to Java ping-pong; exposes it via Accounts.jsm; and
uses it in response to the fxa-content-server message.

mobile/android/base/AccountsHelper.java

@@ -6,6 +6,11 @@
 package org.mozilla.gecko;
 
 import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.accounts.AccountManagerCallback;
+import android.accounts.AccountManagerFuture;
+import android.accounts.AuthenticatorException;
+import android.accounts.OperationCanceledException;
 import android.content.Context;
 import android.content.Intent;
 import android.util.Log;
@@ -22,6 +27,7 @@ import org.mozilla.gecko.util.EventCallback;
 import org.mozilla.gecko.util.NativeEventListener;
 import org.mozilla.gecko.util.NativeJSObject;
 
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URISyntaxException;
 import java.security.GeneralSecurityException;
@@ -48,6 +54,7 @@ public class AccountsHelper implements NativeEventListener {
                 "Accounts:CreateFirefoxAccountFromJSON",
                 "Accounts:UpdateFirefoxAccountFromJSON",
                 "Accounts:Create",
+                "Accounts:DeleteFirefoxAccount",
                 "Accounts:Exist");
     }
 
@@ -61,11 +68,12 @@ public class AccountsHelper implements NativeEventListener {
                 "Accounts:CreateFirefoxAccountFromJSON",
                 "Accounts:UpdateFirefoxAccountFromJSON",
                 "Accounts:Create",
+                "Accounts:DeleteFirefoxAccount",
                 "Accounts:Exist");
     }
 
     @Override
-    public void handleMessage(String event, NativeJSObject message, EventCallback callback) {
+    public void handleMessage(String event, NativeJSObject message, final EventCallback callback) {
         if ("Accounts:CreateFirefoxAccountFromJSON".equals(event)) {
             AndroidFxAccount fxAccount = null;
             try {
@@ -157,6 +165,43 @@ public class AccountsHelper implements NativeEventListener {
             }
             mContext.startActivity(intent);
 
+        } else if ("Accounts:DeleteFirefoxAccount".equals(event)) {
+            try {
+                final Account account = FirefoxAccounts.getFirefoxAccount(mContext);
+                if (account == null) {
+                    Log.w(LOGTAG, "Could not delete Firefox Account since none exists!");
+                    if (callback != null) {
+                        callback.sendError("Could not delete Firefox Account since none exists");
+                    }
+                    return;
+                }
+
+                final AccountManagerCallback<Boolean> accountManagerCallback = new AccountManagerCallback<Boolean>() {
+                    @Override
+                    public void run(AccountManagerFuture<Boolean> future) {
+                        try {
+                            final boolean result = future.getResult();
+                            Log.i(LOGTAG, "Account named like " + Utils.obfuscateEmail(account.name) + " removed: " + result);
+                            if (callback != null) {
+                                callback.sendSuccess(result);
+                            }
+                        } catch (OperationCanceledException | IOException | AuthenticatorException e) {
+                            if (callback != null) {
+                                callback.sendError("Could not delete Firefox Account: " + e.toString());
+                            }
+                        }
+                    }
+                };
+
+                AccountManager.get(mContext).removeAccount(account, accountManagerCallback, null);
+            } catch (Exception e) {
+                Log.w(LOGTAG, "Got exception updating Firefox Account from JSON; ignoring.", e);
+                if (callback != null) {
+                    callback.sendError("Could not update Firefox Account from JSON: " + e.toString());
+                    return;
+                }
+            }
+
         } else if ("Accounts:Exist".equals(event)) {
             if (callback == null) {
                 Log.w(LOGTAG, "Accounts:Exist requires a callback");

mobile/android/modules/Accounts.jsm

@@ -131,5 +131,18 @@ let Accounts = Object.freeze({
       delete data.exists;
       return data;
     });
+  },
+
+  /**
+   * Delete an existing Android Firefox Account.
+   *
+   * It is an error if no Android Account exists.
+   *
+   * Returns a Promise that resolves to a boolean indicating success.
+   */
+  deleteFirefoxAccount: function () {
+    return Messaging.sendRequestForResult({
+      type: "Accounts:DeleteFirefoxAccount",
+    });
   }
 });

mobile/android/modules/FxAccountsWebChannel.jsm

@@ -28,6 +28,7 @@ const COMMAND_LOADED               = "fxaccounts:loaded";
 const COMMAND_CAN_LINK_ACCOUNT     = "fxaccounts:can_link_account";
 const COMMAND_LOGIN                = "fxaccounts:login";
 const COMMAND_CHANGE_PASSWORD      = "fxaccounts:change_password";
+const COMMAND_DELETE_ACCOUNT       = "fxaccounts:delete_account";
 
 const PREF_LAST_FXA_USER           = "identity.fxaccounts.lastSignedInUserHash";
 
@@ -315,6 +316,26 @@ this.FxAccountsWebChannel.prototype = {
             });
             break;
 
+          case COMMAND_DELETE_ACCOUNT:
+            // The fxa-content-server has already confirmed the user's intent.
+            // Bombs away.  There's no recovery from failure, and not even a
+            // real need to check an account exists (although we do, for error
+            // messaging only).
+            Accounts.getFirefoxAccount().then(account => {
+              if (!account) {
+                throw new Error("Can't delete non-existent Firefox Account!");
+              }
+              return Accounts.deleteFirefoxAccount().then(success => {
+                if (!success) {
+                  throw new Error("Could not delete Firefox Account!");
+                }
+                log.i("Firefox Account deleted.");
+              });
+            }).catch(e => {
+              log.e(e.toString());
+            });
+            break;
+
           default:
             log.w("Ignoring unrecognized FxAccountsWebChannel command: " + JSON.stringify(command));
             break;