Add setLabeledBy

Summary:
Adding setLabeledBy to style.

In android we would pass a view, but i think working with tags makes more sense (?)
Im happy to hear any other feedback about how better to implement this.

other improvement I see is just add the special labeledBy view tag id, so we wont override it with any other view ids if we would set somethign on it. (But if we are setting labeled by I would think they will know what they are doing (?))

there are two methods:
```
public void setLabeledBy (View label)
and
public void setLabeledBy (View root,
                int virtualDescendantId)
```

As there is a workaround to set this using:

```
Text(
    text = "I'm a text",
    style =
        Style.onInitializeAccessibilityNodeInfo { event ->
              event.superDelegate.onInitializeAccessibilityNodeInfo(
                  event.host, event.info)
              val parentView = event.host.parent as View
              if (placeholderText == null) {
                event.info.setLabeledBy(......)
              }
            }
       )

```
I focused only on the first simplier method

Reviewed By: zielinskimz

Differential Revision: D65419674

fbshipit-source-id: 71519ba442cb9d7327ba7c47c72e31ff557d7ae3

litho-core/src/main/java/com/facebook/litho/CommonProps.kt

@@ -359,6 +359,10 @@ class CommonProps : LayoutProps, Equivalence<CommonProps?> {
     getOrCreateNodeInfo().minDurationBetweenContentChangesMillis = duration
   }
 
+  fun setLabeledBy(viewTag: Any?) {
+    getOrCreateNodeInfo().labeledBy = viewTag
+  }
+
   fun clickable(isClickable: Boolean) {
     getOrCreateNodeInfo().setClickable(isClickable)
   }

litho-core/src/main/java/com/facebook/litho/ComponentAccessibilityDelegate.java

@@ -147,6 +147,14 @@ public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCo
           mNodeInfo.getMinDurationBetweenContentChangesMillis());
     }
 
+    if (mNodeInfo != null && mNodeInfo.getLabeledBy() != null && mountItem != null) {
+      final ComponentContext scopedContext = getComponentContext(mountItem.getRenderTreeNode());
+      final View labeledByView = scopedContext.findViewWithTag(mNodeInfo.getLabeledBy());
+      if (labeledByView != null) {
+        node.setLabeledBy(labeledByView);
+      }
+    }
+
     if (mNodeInfo != null && mNodeInfo.getFocusOrder() != null && mountItem != null) {
       final ComponentContext scopedContext = getComponentContext(mountItem.getRenderTreeNode());
       final FocusOrderModel focusOrder = mNodeInfo.getFocusOrder();

litho-core/src/main/java/com/facebook/litho/NodeInfo.kt

@@ -124,6 +124,7 @@ class NodeInfo : Equivalence<NodeInfo> {
       EventHandler<SendAccessibilityEventUncheckedEvent>? =
       null
   private var _minDurationBetweenContentChangesMillis: Long? = null
+  private var _labeledBy: Any? = null
 
   var visibility: Visibility? = null
     internal set(value) {
@@ -412,6 +413,13 @@ class NodeInfo : Equivalence<NodeInfo> {
       _minDurationBetweenContentChangesMillis = duration
     }
 
+  var labeledBy: Any?
+    get() = _labeledBy
+    set(viewTag) {
+      flags = flags or PFLAG_LABELED_BY_IS_SET
+      _labeledBy = viewTag
+    }
+
   fun needsAccessibilityDelegate(): Boolean =
       _onInitializeAccessibilityEventHandler != null ||
           _onInitializeAccessibilityNodeInfoHandler != null ||
@@ -427,6 +435,7 @@ class NodeInfo : Equivalence<NodeInfo> {
           _accessibilityRole != null ||
           _accessibilityRoleDescription != null ||
           _focusOrder != null ||
+          _labeledBy != null ||
           screenReaderFocusState != SCREEN_READER_FOCUS_UNSET
 
   fun setFocusable(isFocusable: Boolean) {
@@ -822,6 +831,9 @@ class NodeInfo : Equivalence<NodeInfo> {
     if (flags and PFLAG_VISIBILITY_IS_SET != 0L) {
       target.visibility = visibility
     }
+    if (flags and PFLAG_LABELED_BY_IS_SET != 0L) {
+      target.labeledBy = labeledBy
+    }
   }
 
   fun copyInto(target: ViewAttributes) {
@@ -1030,5 +1042,9 @@ class NodeInfo : Equivalence<NodeInfo> {
     // When this flag is set, setMinDurationBetweenContentChangesMillis was explicitly set on this
     // node.
     private const val PFLAG_MIN_DURATION_BETWEEN_CHANGES_IS_SET = 1L shl 36
+
+    // When this flag is set, setLabeledBy was explicitly set on this
+    // node.
+    private const val PFLAG_LABELED_BY_IS_SET = 1L shl 36
   }
 }

litho-core/src/main/java/com/facebook/litho/accessibility/AccessibilityStyles.kt

@@ -61,6 +61,7 @@ internal enum class AccessibilityField : StyleItemField {
   ON_VIRTUAL_VIEW_KEYBOARD_FOCUS_CHANGED,
   SCREEN_READER_FOCUSABLE,
   MIN_DURATION_BETWEEN_CONTENT_CHANGES,
+  LABELED_BY,
 }
 
 @PublishedApi
@@ -114,6 +115,7 @@ internal data class AccessibilityStyleItem(
           commonProps.screenReaderFocusable(value as Boolean)
       AccessibilityField.MIN_DURATION_BETWEEN_CONTENT_CHANGES ->
           commonProps.setMinDurationBetweenContentChangesMillis(value as Long)
+      AccessibilityField.LABELED_BY -> commonProps.setLabeledBy(value)
     }
   }
 }
@@ -325,6 +327,17 @@ inline fun Style.screenReaderFocusable(isFocusable: Boolean): Style =
 inline fun Style.minDurationBetweenContentChangesMillis(duration: Long): Style =
     this + AccessibilityStyleItem(AccessibilityField.MIN_DURATION_BETWEEN_CONTENT_CHANGES, duration)
 
+/**
+ * Sets the view which serves as the label of the view represented by this info for accessibility
+ * purposes.
+ *
+ * @param viewTag The view tag of the view which serves as the label of the view represented by this
+ *
+ * See [android.view.accessibility.AccessibilityNodeInfo.setLabeledBy].
+ */
+inline fun Style.labeledBy(viewTag: Any): Style =
+    this + AccessibilityStyleItem(AccessibilityField.LABELED_BY, viewTag)
+
 /**
  * Enum values for [importantForAccessibility].
  *