Fix issue with null-value OAuth2 tokens for Android.

Currently, AndroidProfileOAuth2TokenServiceHelper crashes if the auth
token returned from the account manager is null. This CL makes it
possible to get null tokens back.

A test is also added, and the test harness is improved to support adding
null auth-tokens.

This is try 2. Original CL reviewed in:
https://chromiumcodereview.appspot.com/20692003

BUG=239491
NOTRY=true

Review URL: https://chromiumcodereview.appspot.com/21436002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@215048 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 44 insertions, 22 deletions

diff --git a/sync/android/java/src/org/chromium/sync/signin/AccountManagerHelper.java b/sync/android/java/src/org/chromium/sync/signin/AccountManagerHelper.java
index 3ed9a22..01ad162 100644
--- a/sync/android/java/src/org/chromium/sync/signin/AccountManagerHelper.java
+++ b/sync/android/java/src/org/chromium/sync/signin/AccountManagerHelper.java
@@ -20,6 +20,7 @@ import android.os.AsyncTask;
 import android.os.Bundle;
 import android.util.Log;
 
+import org.chromium.base.ThreadUtils;
 import org.chromium.net.NetworkChangeNotifier;
 
 import java.io.IOException;
@@ -250,29 +251,44 @@ public class AccountManagerHelper {
         }
         final AccountManagerFuture<Bundle> finalFuture = future;
         errorEncountered.set(false);
-        new AsyncTask<Void, Void, String>() {
-            @Override
-            public String doInBackground(Void... params) {
-                return getAuthTokenInner(finalFuture, errorEncountered);
-            }
-            @Override
-            public void onPostExecute(String authToken) {
-                if (authToken != null || !errorEncountered.get() ||
-                        numTries.incrementAndGet() == MAX_TRIES ||
-                        !NetworkChangeNotifier.isInitialized()) {
-                    callback.tokenAvailable(authToken);
-                    return;
-                }
-                if (retry == null) {
-                    ConnectionRetry newRetry = new ConnectionRetry(account, authTokenType, callback,
-                            numTries, errorEncountered);
-                    NetworkChangeNotifier.addConnectionTypeObserver(newRetry);
+
+        // On ICS onPostExecute is never called when running an AsyncTask from a different thread
+        // than the UI thread.
+        if (ThreadUtils.runningOnUiThread()) {
+            new AsyncTask<Void, Void, String>() {
+                @Override
+                public String doInBackground(Void... params) {
+                    return getAuthTokenInner(finalFuture, errorEncountered);
                 }
-                else {
-                    NetworkChangeNotifier.addConnectionTypeObserver(retry);
+                @Override
+                public void onPostExecute(String authToken) {
+                    onGotAuthTokenResult(account, authTokenType, authToken, callback, numTries,
+                            errorEncountered, retry);
                 }
-            }
-        }.execute();
+            }.execute();
+        } else {
+            String authToken = getAuthTokenInner(finalFuture, errorEncountered);
+            onGotAuthTokenResult(account, authTokenType, authToken, callback, numTries,
+                    errorEncountered, retry);
+        }
+    }
+
+    private void onGotAuthTokenResult(Account account, String authTokenType, String authToken,
+            GetAuthTokenCallback callback, AtomicInteger numTries, AtomicBoolean errorEncountered,
+            ConnectionRetry retry) {
+        if (authToken != null || !errorEncountered.get() ||
+                numTries.incrementAndGet() == MAX_TRIES ||
+                !NetworkChangeNotifier.isInitialized()) {
+            callback.tokenAvailable(authToken);
+            return;
+        }
+        if (retry == null) {
+            ConnectionRetry newRetry = new ConnectionRetry(account, authTokenType, callback,
+                    numTries, errorEncountered);
+            NetworkChangeNotifier.addConnectionTypeObserver(newRetry);
+        } else {
+            NetworkChangeNotifier.addConnectionTypeObserver(retry);
+        }
     }
 
     /**
diff --git a/sync/test/android/javatests/src/org/chromium/sync/test/util/AccountHolder.java b/sync/test/android/javatests/src/org/chromium/sync/test/util/AccountHolder.java
index 1b346a1..cff504c 100644
--- a/sync/test/android/javatests/src/org/chromium/sync/test/util/AccountHolder.java
+++ b/sync/test/android/javatests/src/org/chromium/sync/test/util/AccountHolder.java
@@ -48,6 +48,10 @@ public class AccountHolder {
         return mPassword;
     }
 
+    public boolean hasAuthTokenRegistered(String authTokenType) {
+        return mAuthTokens.containsKey(authTokenType);
+    }
+
     public String getAuthToken(String authTokenType) {
         return mAuthTokens.get(authTokenType);
     }
diff --git a/sync/test/android/javatests/src/org/chromium/sync/test/util/MockAccountManager.java b/sync/test/android/javatests/src/org/chromium/sync/test/util/MockAccountManager.java
index da16fae..cb330b8 100644
--- a/sync/test/android/javatests/src/org/chromium/sync/test/util/MockAccountManager.java
+++ b/sync/test/android/javatests/src/org/chromium/sync/test/util/MockAccountManager.java
@@ -264,7 +264,9 @@ public class MockAccountManager implements AccountManagerDelegate {
 
     private String internalGenerateAndStoreAuthToken(AccountHolder ah, String authTokenType) {
         synchronized (mAccounts) {
-            if (ah.getAuthToken(authTokenType) == null) {
+            // Some tests register auth tokens with value null, and those should be preserved.
+            if (!ah.hasAuthTokenRegistered(authTokenType) &&
+                    ah.getAuthToken(authTokenType) == null) {
                 // No authtoken registered. Need to create one.
                 String authToken = UUID.randomUUID().toString();
                 Log.d(TAG, "Created new auth token for " + ah.getAccount() +