Breaking: Move ReactClippingViewGroup + Helper to uimanager package

Summary: This is to be able to depend on ReactClippingViewGroup from BaseViewManager. Devs using ReactClippingViewGroup may need to update their imports when updating past this commit.

Reviewed By: lexs

Differential Revision: D3835328

fbshipit-source-id: 290c08b130d837e553b68a90377bd9a30b7ec6dc

ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactClippingViewGroupHelper.java

@@ -0,0 +1,61 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.react.uimanager;
+
+import javax.annotation.concurrent.NotThreadSafe;
+
+import android.graphics.Rect;
+import android.view.View;
+import android.view.ViewParent;
+
+/**
+ * Provides implementation of common tasks for view and it's view manager supporting property
+ * {@code removeClippedSubviews}.
+ */
+@NotThreadSafe
+public class ReactClippingViewGroupHelper {
+
+  public static final String PROP_REMOVE_CLIPPED_SUBVIEWS = "removeClippedSubviews";
+
+  private static final Rect sHelperRect = new Rect();
+
+  /**
+   * Can be used by view that support {@code removeClippedSubviews} property to calculate area that
+   * given {@param view} should be clipped to based on the clipping rectangle of it's parent in
+   * case when parent is also set to clip it's children.
+   *
+   * @param view view that we want to calculate clipping rect for
+   * @param outputRect where the calculated rectangle will be written
+   */
+  public static void calculateClippingRect(View view, Rect outputRect) {
+    ViewParent parent = view.getParent();
+    if (parent == null) {
+      outputRect.setEmpty();
+      return;
+    } else if (parent instanceof ReactClippingViewGroup) {
+      ReactClippingViewGroup clippingViewGroup = (ReactClippingViewGroup) parent;
+      if (clippingViewGroup.getRemoveClippedSubviews()) {
+        clippingViewGroup.getClippingRect(sHelperRect);
+        // Intersect the view with the parent's rectangle
+        // This will result in the overlap with coordinates in the parent space
+        if (!sHelperRect.intersect(view.getLeft(), view.getTop(), view.getRight(), view.getBottom())) {
+          outputRect.setEmpty();
+          return;
+        }
+        // Now we move the coordinates to the View's coordinate space
+        sHelperRect.offset(-view.getLeft(), -view.getTop());
+        sHelperRect.offset(view.getScrollX(), view.getScrollY());
+        outputRect.set(sHelperRect);
+        return;
+      }
+    }
+    view.getDrawingRect(outputRect);
+  }
+}