Android ScrollView support for `overflow: visible`

Summary:
ScrollView always clipping children on Android even when `overflow: visible` was specified.
This change just omits the clipping during draw if `overflow: visible` is passed in.
The default is not changed (from hidden to visible) in case there is a performance impact.
Android now matches iOS in behavior. This helps with issue #21116 and resolves #14416.

Reviewed By: shergin

Differential Revision: D9952096

fbshipit-source-id: 367afe33ee7ff0fdc5aa1074d239883aa289888a

ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java

@@ -27,10 +27,11 @@ import android.widget.OverScroller;
 
 import com.facebook.infer.annotation.Assertions;
 import com.facebook.react.common.ReactConstants;
+import com.facebook.react.uimanager.events.NativeGestureUtil;
 import com.facebook.react.uimanager.MeasureSpecAssertions;
 import com.facebook.react.uimanager.ReactClippingViewGroup;
 import com.facebook.react.uimanager.ReactClippingViewGroupHelper;
-import com.facebook.react.uimanager.events.NativeGestureUtil;
+import com.facebook.react.uimanager.ViewProps;
 import com.facebook.react.views.view.ReactViewBackgroundManager;
 
 import java.lang.reflect.Field;
@@ -55,6 +56,7 @@ public class ReactHorizontalScrollView extends HorizontalScrollView implements
 
   private boolean mActivelyScrolling;
   private @Nullable Rect mClippingRect;
+  private @Nullable String mOverflow = ViewProps.HIDDEN;
   private boolean mDragging;
   private boolean mPagingEnabled = false;
   private @Nullable Runnable mPostTouchRunnable;
@@ -181,10 +183,23 @@ public class ReactHorizontalScrollView extends HorizontalScrollView implements
     awakenScrollBars();
   }
 
+  public void setOverflow(String overflow) {
+    mOverflow = overflow;
+    invalidate();
+  }
+
   @Override
   protected void onDraw(Canvas canvas) {
     getDrawingRect(mRect);
-    canvas.clipRect(mRect);
+
+    switch (mOverflow) {
+      case ViewProps.VISIBLE:
+        break;
+      case ViewProps.HIDDEN:
+        canvas.clipRect(mRect);
+        break;
+    }
+
     super.onDraw(canvas);
   }
 

ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollViewManager.java

@@ -250,4 +250,9 @@ public class ReactHorizontalScrollViewManager
     float alphaComponent = color == null ? YogaConstants.UNDEFINED : (float) ((int)color >>> 24);
     view.setBorderColor(SPACING_TYPES[index], rgbComponent, alphaComponent);
   }
+
+  @ReactProp(name = "overflow")
+  public void setOverflow(ReactHorizontalScrollView view, @Nullable String overflow) {
+    view.setOverflow(overflow);
+  }
 }

ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java

@@ -24,10 +24,11 @@ import android.widget.ScrollView;
 import com.facebook.infer.annotation.Assertions;
 import com.facebook.react.bridge.ReactContext;
 import com.facebook.react.common.ReactConstants;
+import com.facebook.react.uimanager.events.NativeGestureUtil;
 import com.facebook.react.uimanager.MeasureSpecAssertions;
 import com.facebook.react.uimanager.ReactClippingViewGroup;
 import com.facebook.react.uimanager.ReactClippingViewGroupHelper;
-import com.facebook.react.uimanager.events.NativeGestureUtil;
+import com.facebook.react.uimanager.ViewProps;
 import com.facebook.react.views.view.ReactViewBackgroundManager;
 
 import java.lang.reflect.Field;
@@ -54,6 +55,7 @@ public class ReactScrollView extends ScrollView implements ReactClippingViewGrou
 
   private boolean mActivelyScrolling;
   private @Nullable Rect mClippingRect;
+  private @Nullable String mOverflow = ViewProps.HIDDEN;
   private boolean mDragging;
   private boolean mPagingEnabled = false;
   private @Nullable Runnable mPostTouchRunnable;
@@ -169,6 +171,11 @@ public class ReactScrollView extends ScrollView implements ReactClippingViewGrou
     awakenScrollBars();
   }
 
+  public void setOverflow(String overflow) {
+    mOverflow = overflow;
+    invalidate();
+  }
+
   @Override
   protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
     MeasureSpecAssertions.assertExplicitMeasureSpec(widthMeasureSpec, heightMeasureSpec);
@@ -373,7 +380,15 @@ public class ReactScrollView extends ScrollView implements ReactClippingViewGrou
       }
     }
     getDrawingRect(mRect);
-    canvas.clipRect(mRect);
+
+    switch (mOverflow) {
+      case ViewProps.VISIBLE:
+        break;
+      case ViewProps.HIDDEN:
+        canvas.clipRect(mRect);
+        break;
+    }
+
     super.draw(canvas);
   }
 

ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollViewManager.java

@@ -245,6 +245,11 @@ public class ReactScrollViewManager
     view.setBorderColor(SPACING_TYPES[index], rgbComponent, alphaComponent);
   }
 
+  @ReactProp(name = "overflow")
+  public void setOverflow(ReactScrollView view, @Nullable String overflow) {
+    view.setOverflow(overflow);
+  }
+
   @Override
   public void scrollToEnd(
       ReactScrollView scrollView,