Support ScrollAway in ReactScrollView

Summary:
Support ScrollAway in ReactScrollView for Fabric/non-Fabric.

Changelog: [Android][Added] Support for ScrollAway native nav bars added to ReactScrollView

Reviewed By: mdvacca

Differential Revision: D28308855

fbshipit-source-id: 9a922159ef50fb7c8e9c484a4b97ca57ab248496

ReactCommon/react/renderer/components/scrollview/ScrollViewShadowNode.cpp

@@ -34,7 +34,7 @@ void ScrollViewShadowNode::updateStateIfNeeded() {
 void ScrollViewShadowNode::updateScrollContentOffsetIfNeeded() {
 #ifndef ANDROID
   if (getLayoutMetrics().layoutDirection == LayoutDirection::RightToLeft) {
-    // Yoga place `contentView` on the right side of `scrollView` when RTL
+    // Yoga places `contentView` on the right side of `scrollView` when RTL
     // layout is enforced. To correct for this, in RTL setting, correct the
     // frame's origin. React Native Classic does this as well in
     // `RCTScrollContentShadowView.m`.
@@ -58,8 +58,9 @@ void ScrollViewShadowNode::layout(LayoutContext layoutContext) {
 }
 
 Point ScrollViewShadowNode::getContentOriginOffset() const {
-  auto contentOffset = getStateData().contentOffset;
-  return {-contentOffset.x, -contentOffset.y};
+  auto stateData = getStateData();
+  auto contentOffset = stateData.contentOffset;
+  return {-contentOffset.x, -contentOffset.y + stateData.scrollAwayPaddingTop};
 }
 
 } // namespace react

ReactCommon/react/renderer/components/scrollview/ScrollViewState.h

@@ -25,6 +25,7 @@ class ScrollViewState final {
  public:
   Point contentOffset;
   Rect contentBoundingRect;
+  int scrollAwayPaddingTop;
 
   /*
    * Returns size of scrollable area.
@@ -37,11 +38,13 @@ class ScrollViewState final {
       : contentOffset(
             {(Float)data["contentOffsetLeft"].getDouble(),
              (Float)data["contentOffsetTop"].getDouble()}),
-        contentBoundingRect({}){};
+        contentBoundingRect({}),
+        scrollAwayPaddingTop((Float)data["scrollAwayPaddingTop"].getDouble()){};
 
   folly::dynamic getDynamic() const {
     return folly::dynamic::object("contentOffsetLeft", contentOffset.x)(
-        "contentOffsetTop", contentOffset.y);
+        "contentOffsetTop", contentOffset.y)(
+        "scrollAwayPaddingTop", scrollAwayPaddingTop);
   };
   MapBuffer getMapBuffer() const {
     return MapBufferBuilder::EMPTY();

ReactCommon/react/renderer/core/tests/ConcreteShadowNodeTest.cpp

@@ -26,7 +26,7 @@ TEST(ConcreteShadowNodeTest, testSetStateData) {
 
   auto shadowNode = builder.build(element);
 
-  shadowNode->setStateData({{10, 11}, {{21, 22}, {301, 302}}});
+  shadowNode->setStateData({{10, 11}, {{21, 22}, {301, 302}}, 0});
 
   EXPECT_NE(
       shadowNode->getState(), shadowNode->getFamily().getMostRecentState());