Fix lint issues

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/Camera.java

@@ -130,7 +130,7 @@ class Camera
   CameraDeviceWrapper cameraDevice;
   CameraCaptureSession captureSession;
   private ImageReader pictureImageReader;
-  private ImageStreamReader imageStreamReader;
+  ImageStreamReader imageStreamReader;
   /** {@link CaptureRequest.Builder} for the camera preview */
   CaptureRequest.Builder previewRequestBuilder;
 
@@ -1199,7 +1199,7 @@ public void onCancel(Object o) {
         });
   }
 
-  private void setImageStreamImageAvailableListener(final EventChannel.EventSink imageStreamSink) {
+  void setImageStreamImageAvailableListener(final EventChannel.EventSink imageStreamSink) {
     if (imageStreamReader == null) {
       return;
     }

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/media/ImageStreamReader.java

@@ -41,7 +41,7 @@ public class ImageStreamReader {
    */
   @VisibleForTesting
   public ImageStreamReader(
-      ImageReader imageReader, int dartImageFormat, ImageStreamReaderUtils imageStreamReaderUtils) {
+          @NonNull ImageReader imageReader, int dartImageFormat, @NonNull ImageStreamReaderUtils imageStreamReaderUtils) {
     this.imageReader = imageReader;
     this.dartImageFormat = dartImageFormat;
     this.imageStreamReaderUtils = imageStreamReaderUtils;
@@ -91,8 +91,8 @@ public static int computeStreamImageFormat(int dartImageFormat) {
   @VisibleForTesting
   public void onImageAvailable(
       @NonNull Image image,
-      CameraCaptureProperties captureProps,
-      EventChannel.EventSink imageStreamSink) {
+      @NonNull CameraCaptureProperties captureProps,
+      @NonNull EventChannel.EventSink imageStreamSink) {
     try {
       Map<String, Object> imageBuffer = new HashMap<>();
 
@@ -138,6 +138,7 @@ public void onImageAvailable(
    * @param image - the image to process.
    * @return parsed map describing the image planes to be sent to dart.
    */
+  @NonNull
   public List<Map<String, Object>> parsePlanesForYuvOrJpeg(@NonNull Image image) {
     List<Map<String, Object>> planes = new ArrayList<>();
 
@@ -164,6 +165,7 @@ public List<Map<String, Object>> parsePlanesForYuvOrJpeg(@NonNull Image image) {
    * @param image - the image to process.
    * @return parsed map describing the image planes to be sent to dart.
    */
+  @NonNull
   public List<Map<String, Object>> parsePlanesForNv21(@NonNull Image image) {
     List<Map<String, Object>> planes = new ArrayList<>();
 
@@ -181,6 +183,7 @@ public List<Map<String, Object>> parsePlanesForNv21(@NonNull Image image) {
   }
 
   /** Returns the image reader surface. */
+  @NonNull
   public Surface getSurface() {
     return imageReader.getSurface();
   }
@@ -194,9 +197,9 @@ public Surface getSurface() {
    * @param handler is generally the background handler of the camera as {@link Handler}
    */
   public void subscribeListener(
-      CameraCaptureProperties captureProps,
-      EventChannel.EventSink imageStreamSink,
-      Handler handler) {
+          @NonNull CameraCaptureProperties captureProps,
+          @NonNull EventChannel.EventSink imageStreamSink,
+          @NonNull Handler handler) {
     imageReader.setOnImageAvailableListener(
         reader -> {
           Image image = reader.acquireNextImage();
@@ -212,7 +215,7 @@ public void subscribeListener(
    *
    * @param handler is generally the background handler of the camera
    */
-  public void removeListener(Handler handler) {
+  public void removeListener(@NonNull Handler handler) {
     imageReader.setOnImageAvailableListener(null, handler);
   }
 

packages/camera/camera_android/android/src/main/java/io/flutter/plugins/camera/media/ImageStreamReaderUtils.java

@@ -31,7 +31,8 @@ public class ImageStreamReaderUtils {
    *
    * <p>https://github.com/googlesamples/mlkit/blob/master/android/vision-quickstart/app/src/main/java/com/google/mlkit/vision/demo/BitmapUtils.java
    */
-  public ByteBuffer yuv420ThreePlanesToNV21(Image.Plane[] yuv420888planes, int width, int height) {
+  @NonNull
+  public ByteBuffer yuv420ThreePlanesToNV21(@NonNull Image.Plane[] yuv420888planes, int width, int height) {
     int imageSize = width * height;
     byte[] out = new byte[imageSize + 2 * (imageSize / 4)];