fixing the result handlers and orientation changes

briar-android/src/org/briarproject/android/BaseActivity.java

...r-android/src/org/briarproject/android/BriarActivity.java

.../src/org/briarproject/android/ChangePasswordActivity.java

...droid/src/org/briarproject/android/NavDrawerActivity.java

...ndroid/src/org/briarproject/android/PasswordActivity.java

...r-android/src/org/briarproject/android/SetupActivity.java

.../briarproject/android/controller/BriarControllerImpl.java

...ject/android/controller/handler/ContextResultHandler.java

...android/controller/handler/DestroyableContextManager.java

...d/controller/handler/UiContextExceptionResultHandler.java

...ct/android/controller/handler/UiContextResultHandler.java

...oid/src/org/briarproject/android/forum/ForumActivity.java

...ndroid/privategroup/creation/BaseGroupInviteActivity.java

...ct/android/privategroup/creation/CreateGroupActivity.java