[Chat] Crash when typing a message while chat is loading

[steenburgh]

Steps to reproduce:

1. Connect your device to a slow wifi network, or turn off 3G/4G. You can also slow down the network speed with an emulator
2. Open the chat tab
3. Before chat finishes loading, enter some text in the chatbox.
4. Chat will crash when it finishes loading.

Other notes:
Chat also appears to sometimes crash the app when the device is unlocked and chat was the last open app. I'm unsure if this crash is related, or exactly how to reproduce the bug as it was pretty rare.

[steenburgh]

This appears to be caused by improper handling of orientation changes, an issue that is likely present in several other activities in our app(but not causing crashes as far as I know). This still needs to be investigated further, but locking orientation to portrait mode appears to be an effective temporary fix for this issue as most users don't have a reason to use theapp in landscape mode.