android: Rework request completion notification

The current implementation of CameraDevice::requestComplete() which
handles event notification and calls the framework capture result
callback does not handle error notification precisely enough.

In detail:
- Error notification is an asynchronous callback that has to be notified
  to the framework as soon as an error condition is detected, and it
  independent from the process_capture_result() callback

- Error notification requires the HAL to report the precise error cause,
  by specifying the correct CAMERA3_MSG_ERROR_* error code.

The current implementation only notifies errors of type
CAMERA3_MSG_ERROR_REQUEST at the end of the procedure, before the
callback invocation.

Rework the procedure to:

- Notify CAMERA3_MSG_ERROR_DEVICE and perform library tear-down in case
  a Fatal error is detected

- Notify CAMERA3_MSG_ERROR_REQUEST if the libcamera::Request::status is
  different than RequestCompleted and immediately call
  process_capture_result() with all buffers in error state.

- Notify the shutter event as soon as possible

- Notify CAMERA3_MSG_ERROR_RESULT in case the metadata cannot be
  generated correctly and call process_capture_result() with the right
  buffer state regardless of metadata availability.

- Notify CAMERA3_MSG_ERROR_BUFFER for buffers whose post-processing
  failed

While at it, return the CameraStream buffer by calling
cameraStream->putBuffer() regardless of the post-processing result.

No regression detected when running CTS in LIMITED mode.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/android/camera_device.h

@@ -101,7 +101,8 @@ private:
 
 	libcamera::FrameBuffer *createFrameBuffer(const buffer_handle_t camera3buffer);
 	void notifyShutter(uint32_t frameNumber, uint64_t timestamp);
-	void notifyError(uint32_t frameNumber, camera3_stream_t *stream);
+	void notifyError(uint32_t frameNumber, camera3_stream_t *stream,
+			 camera3_error_msg_code code);
 	std::unique_ptr<CameraMetadata> requestTemplatePreview();
 	std::unique_ptr<CameraMetadata> requestTemplateVideo();
 	libcamera::PixelFormat toPixelFormat(int format) const;