This adds a new `wine/ime.h` header, to share the `IMEPRIVATE` structure between `imm32`, `winex11` and `winemac`. This structure will be internal to `imm32` ultimately, but I intend to keep the header to define a new internal interface for driver to call back into `imm32` (through the UI window), and for a new interface to call from `imm32` into host IME implemented by the drivers.
-- v2: imm32: Remove unnecessary HIMC check in IME UI window proc. imm32: Call DefWindowProcW from IME UI for unhandled messages. imm32: Cleanup default IME UI window proc traces. winemac: Use the default IME UI window proc implementation. winex11: Move IME UI proc to default IME implementation. winex11: Cleanup spaces in IME UI window proc.