Use AcquireToken to force refresh token to be saved in the cache

Fixes #36
When using the AquireTokenByRefreshToken(...) method, the underlying ADAL
system does not guarentee the token will be saved for future use in the
TokenCacheStore.  Tracing into the AuthenticationContext implementation,
refreshToken(..., final boolean useCache) is getting set to false in all
of the 'refresh token` scenarios.  Using aquireToken and then depending on
the Prompt settings seems to be the best course of action to mitigate this
issue.  Note: it is not clear why this behavoir changed.

Author: Peter Nied

onedrivesdk/src/main/java/com/onedrive/sdk/authentication/ADALAuthenticator.java

@@ -295,7 +295,7 @@ public synchronized IAccountInfo login(final String emailAddressHint) throws Cli
 
         // Request a fresh auth token for the OneDrive service.
         final AuthenticationResult oneDriveServiceAuthToken =
-                getOneDriveServiceAuthResult(discoveryServiceAuthToken, oneDriveServiceInfo);
+                getOneDriveServiceAuthResult(oneDriveServiceInfo);
 
         // Get the OneDrive auth token and save a reference to it.
         final String serviceInfoAsString = mHttpProvider.getSerializer()
@@ -591,12 +591,10 @@ private ServiceInfo getOneDriveServiceInfoFromDiscoveryService(final String acce
 
     /**
      * Gets the authentication token for the OneDrive service.
-     * @param authenticationResult The authentication result from the Discovery Service.
      * @param oneDriveServiceInfo The OneDrive services info.
      * @return The authentication result for this OneDrive service.
      */
-    private AuthenticationResult getOneDriveServiceAuthResult(final AuthenticationResult authenticationResult,
-                                                              final ServiceInfo oneDriveServiceInfo) {
+    private AuthenticationResult getOneDriveServiceAuthResult(final ServiceInfo oneDriveServiceInfo) {
         final SimpleWaiter authorityCallbackWaiter = new SimpleWaiter();
         final AtomicReference<ClientException> error = new AtomicReference<>();
         final AtomicReference<AuthenticationResult> oneDriveServiceAuthToken = new AtomicReference<>();
@@ -623,14 +621,13 @@ public void onError(final Exception e) {
                 authorityCallbackWaiter.signal();
             }
         };
-        final String refreshToken = authenticationResult.getRefreshToken();
-
         mLogger.logDebug("Starting OneDrive resource refresh token request");
-        mAdalContext.acquireTokenByRefreshToken(
-                                                   refreshToken,
-                                                   getClientId(),
-                                                   oneDriveServiceInfo.serviceResourceId,
-                                                   authorityCallback);
+        mAdalContext.acquireToken(mActivity,
+                                  oneDriveServiceInfo.serviceResourceId,
+                                  getClientId(),
+                                  getRedirectUrl(),
+                                  PromptBehavior.Auto,
+                                  authorityCallback);
 
         mLogger.logDebug("Waiting for token refresh");
         authorityCallbackWaiter.waitForSignal();