Called via webkit.input_method_context.InputMethodContext.filterKeyEvent on every
key press or release event. Every non-trivial input method needs to
override this in order to implement the mapping from key events to text.
A return value of true indicates to the caller that the event was
consumed by the input method. In that case, the #WebKitInputMethodContext::committed
signal should be emitted upon completion of a key sequence to pass the
resulting text back to the editable element. Alternatively, false may be
returned to indicate that the event wasn’t handled by the input method.
Called via webkit.input_method_context.InputMethodContext.filterKeyEvent on every key press or release event. Every non-trivial input method needs to override this in order to implement the mapping from key events to text. A return value of true indicates to the caller that the event was consumed by the input method. In that case, the #WebKitInputMethodContext::committed signal should be emitted upon completion of a key sequence to pass the resulting text back to the editable element. Alternatively, false may be returned to indicate that the event wasn’t handled by the input method.