Bug 1036075 - [L10n] Keyboard goes CAPS LOCK after typing 100

characters and selecting a suggestion.
What happens now if the user backspaces 100 times?  We will think that the text field is empty and not allow the user to backspace any further.

I think we need to call inputContext.getText() and wait for that promise to resolve to get the complete text, like we do in keyboard.js before calling activate().

It seems to me that the mozKeyboard API is flawed in this case, since the cursor can be outside of the range of the text it returns.