Removed NestedScrollView

NestedScrollView is now on a diferrent repository, it will also serve as
more general purpose to other different packages that uses
CoordinatorLayout and others stuff.

NestedScrollView is NOT a required dependency, since the anchor point
has been implemented, once the BottomSheet already scrolls itself,
the NestedScrollView is only useful when you are using the BottomSheet
with anchorPoint disable and want to add some nested scroll
(see the NestedScrollView example view)

Now you have to install and attach the NestedScrollView manually on componentDidMount

```
  componentDidMount() {
    this.bottomSheet.attachNestedScrollChild(this.nestedScroll)
  }
```

See the repository for installation instructions https://github.com/cesardeazevedo/react-native-nested-scroll-view
And the NestedScrollView example https://github.com/cesardeazevedo/react-native-bottom-sheet-behavior/blob/master/example/views/NestedScrollView.js

Author: cesardeazevedo

android/src/main/java/com/bottomsheetbehavior/BottomSheetBehaviorManager.java

@@ -2,8 +2,10 @@
 
 import android.support.annotation.NonNull;
 import android.support.v4.view.ViewCompat;
+import android.support.v4.widget.NestedScrollView;
 import android.view.MotionEvent;
 import android.view.View;
+import android.view.ViewGroup;
 
 import com.facebook.react.bridge.Arguments;
 import com.facebook.react.bridge.JSApplicationIllegalArgumentException;
@@ -25,6 +27,7 @@ public class BottomSheetBehaviorManager extends ViewGroupManager<BottomSheetBeha
 
     public static final int COMMAND_SET_REQUEST_LAYOUT = 1;
     public static final int COMMAND_SET_BOTTOM_SHEET_STATE = 2;
+    public static final int COMMAND_ATTACH_NESTED_SCROLL_CHILD = 3;
 
     @Override
     public String getName() {
@@ -71,44 +74,12 @@ public void setElevation(BottomSheetBehaviorView view, float elevation) {
         view.setBottomSheetElevation(elevation);
     }
 
-    /**
-     * BottomSheetBehaviorView inherits a NestedScrollView in order to work
-     * with the anchor point, but it breaks any ReactNestedScrollView child,
-     * so we are changing the behavior of ReactNestedScrollView to disable
-     * the nested scroll of the bottom sheet, and enable when the child scroll
-     * reaches the top offset.
-     */
-    @Override
-    public void addView(final BottomSheetBehaviorView parent, View child, int index) {
-        super.addView(parent, child, index);
-
-        final ReactNestedScrollView nestedScroll =
-                (ReactNestedScrollView) parent.findViewWithTag(ReactNestedScrollView.TAG);
-
-        if (nestedScroll != null) {
-            nestedScroll.setOnTouchListener(new View.OnTouchListener() {
-                @Override
-                public boolean onTouch(View v, MotionEvent event) {
-                    int action = event.getAction();
-                    if (action == MotionEvent.ACTION_MOVE) {
-                        if (nestedScroll.computeVerticalScrollOffset() == 0) {
-                            parent.startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
-                        } else {
-                            parent.stopNestedScroll();
-                        }
-                    }
-
-                    return nestedScroll.onTouchEvent(event);
-                }
-            });
-        }
-    }
-
     @Override
     public Map<String, Integer> getCommandsMap() {
         return MapBuilder
           .of("setRequestLayout", COMMAND_SET_REQUEST_LAYOUT,
-              "setBottomSheetState", COMMAND_SET_BOTTOM_SHEET_STATE);
+              "setBottomSheetState", COMMAND_SET_BOTTOM_SHEET_STATE,
+              "attachNestedScrollChild", COMMAND_ATTACH_NESTED_SCROLL_CHILD);
     }
 
     @Nullable
@@ -134,13 +105,21 @@ public Map<String, Object> getExportedCustomBubblingEventTypeConstants() {
     public void receiveCommand(BottomSheetBehaviorView view, int commandType, @Nullable ReadableArray args) {
         switch (commandType) {
           case COMMAND_SET_REQUEST_LAYOUT:
-            setRequestLayout(view);
-            return;
+              setRequestLayout(view);
+              return;
           case COMMAND_SET_BOTTOM_SHEET_STATE:
-            setBottomSheetState(view, args);
-            return;
+              setBottomSheetState(view, args);
+              return;
+          case COMMAND_ATTACH_NESTED_SCROLL_CHILD:
+              int nestedScrollId = args.getInt(0);
+              ViewGroup child = (ViewGroup) view.getRootView().findViewById(nestedScrollId);
+              if (child != null && child instanceof NestedScrollView) {
+                  this.attachNestedScrollChild(view, (NestedScrollView) child);
+              }
+              return;
+
           default:
-            throw new JSApplicationIllegalArgumentException("Invalid Command");
+              throw new JSApplicationIllegalArgumentException("Invalid Command");
         }
     }
 
@@ -155,6 +134,30 @@ private void setBottomSheetState(BottomSheetBehaviorView view, @Nullable Readabl
         }
     }
 
+    /**
+     * BottomSheetBehaviorView inherits a NestedScrollView in order to work
+     * with the anchor point, but it breaks any ReactNestedScrollView child,
+     * so we are changing the behavior of ReactNestedScrollView to disable
+     * the nested scroll of the bottom sheet, and enable when the child scroll
+     * reaches the top offset.
+     */
+    private void attachNestedScrollChild(final BottomSheetBehaviorView parent, final NestedScrollView nestedScroll) {
+        nestedScroll.setOnTouchListener(new View.OnTouchListener() {
+            @Override
+            public boolean onTouch(View v, MotionEvent event) {
+                int action = event.getAction();
+                if (action == MotionEvent.ACTION_MOVE) {
+                    if (nestedScroll.computeVerticalScrollOffset() == 0) {
+                        parent.startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL);
+                    } else {
+                        parent.stopNestedScroll();
+                    }
+                }
+                return nestedScroll.onTouchEvent(event);
+            }
+        });
+    }
+
     public class BottomSheetBehaviorListener extends RNBottomSheetBehavior.BottomSheetCallback {
         @Override
         public void onStateChanged(@NonNull View bottomSheet, int newState) {

android/src/main/java/com/bottomsheetbehavior/BottomSheetBehaviorPackage.java

@@ -31,8 +31,7 @@ public List<ViewManager> createViewManagers(ReactApplicationContext reactApplica
                 new BottomSheetBehaviorManager(),
                 new BackdropBottomSheetManager(),
                 new CoordinatorLayoutManager(),
-                new FloatingActionButtonManager(),
-                new ReactNestedScrollViewManager()
+                new FloatingActionButtonManager()
         );
     }
 }