RN picker - fix types in AndroidDialogPickerManagerInterface

Summary:
according to [this crash report](https://our.intern.facebook.com/intern/logview/details/facebook_android_crashes/7ba7056481015482c6166d65cb97e49d/?trace_key=1506fe36a70dd5e50cdc8968f6317f27), `value` was throwing an NPE despite being null-checked. this is because it was an `int` rather than an `Integer`, so the null check wasn't working

Changelog: Fix types in AndroidDialogPickerManagerInterface

Reviewed By: mdvacca

Differential Revision: D20646343

fbshipit-source-id: a27587e0a48f5782bcf5ffddb604018218e65206

Author: Eddie Dugan

ReactAndroid/src/main/java/com/facebook/react/viewmanagers/AndroidDialogPickerManagerInterface.java

@@ -15,7 +15,7 @@
 
 public interface AndroidDialogPickerManagerInterface<T extends View> {
   void setColor(T view, @Nullable Integer value);
-  void setBackgroundColor(T view, @Nullable int value);
+  void setBackgroundColor(T view, @Nullable Integer value);
   void setEnabled(T view, boolean value);
   void setItems(T view, @Nullable ReadableArray value);
   void setPrompt(T view, @Nullable String value);

ReactAndroid/src/main/java/com/facebook/react/views/picker/ReactDialogPickerManager.java

@@ -9,6 +9,7 @@
 
 import android.widget.Spinner;
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import com.facebook.react.module.annotations.ReactModule;
 import com.facebook.react.uimanager.ThemedReactContext;
 import com.facebook.react.uimanager.ViewManagerDelegate;
@@ -44,7 +45,7 @@ protected ViewManagerDelegate<ReactPicker> getDelegate() {
   }
 
   @Override
-  public void setBackgroundColor(@NonNull ReactPicker view, int backgroundColor) {
+  public void setBackgroundColor(@NonNull ReactPicker view, @Nullable Integer backgroundColor) {
     view.setStagedBackgroundColor(backgroundColor);
   }
 }