Skip A11Y sanity check for keyboard navigation

Summary:
As external keyboard cannot be detected by the current API:

https://www.internalfb.com/code/fbsource/[details]/fbandroid/libraries/components/litho-core/src/main/java/com/facebook/litho/AccessibilityUtils.kt?lines=32-35

It makes Litho will not create `AccessibilityDelegate` for each host whenever A11Y is not enabled, which ends up that keyboard navigation doesn't work at all.

Quote from Brett:
> Otherwise, I think your best bet is to observe connections for keyboards and  change the behavior accordingly. As far as I know this requires a change to the activity in the AndroidManifest, so wouldn’t be something that you could fix in Litho alone. Though most of the activities in the FB4a manifest appear to have the needed property already.

I also ran QE to create host for each component which did see a lot of perf regressions as we expected(https://fburl.com/deltoid3/gfny45o5). It's probably hard for us to ship this.

So for now, I would recommend just skip this sanity check for host, which only works for components that have A11Y enabled as well as focus event handlers. (Otherwise, there's no point to enable keyboard navigation for this component from my understanding.)

Reviewed By: adityasharat

Differential Revision: D69053388

fbshipit-source-id: cfe24bab0948e7f2ef8c1c7544122c956a53c87b

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

@@ -245,7 +245,7 @@ open class ComponentHost(
     setWillNotDraw(ComponentsConfiguration.defaultInstance.enableHostWillNotDraw)
     isChildrenDrawingOrderEnabled = true
     refreshAccessibilityDelegatesIfNeeded(
-        ComponentsConfiguration.enableA11Y || isAccessibilityEnabled(context))
+        ComponentsConfiguration.skipA11YValidationForKeyboard || isAccessibilityEnabled(context))
   }
 
   override fun mount(index: Int, mountItem: MountItem) {
@@ -438,7 +438,7 @@ open class ComponentHost(
     super.setTag(key, tag)
     if (key == COMPONENT_NODE_INFO_ID && tag != null) {
       refreshAccessibilityDelegatesIfNeeded(
-          ComponentsConfiguration.enableA11Y || isAccessibilityEnabled(context))
+          ComponentsConfiguration.skipA11YValidationForKeyboard || isAccessibilityEnabled(context))
       if (componentAccessibilityDelegate != null) {
         (tag as? NodeInfo)?.let { componentAccessibilityDelegate?.setNodeInfo(it) }
       }

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

@@ -37,7 +37,6 @@ import com.facebook.litho.CommonProps.DefaultLayoutProps
 import com.facebook.litho.ComponentHostUtils.maybeSetDrawableState
 import com.facebook.litho.Transition.TransitionKeyType
 import com.facebook.litho.annotations.ImportantForAccessibility
-import com.facebook.litho.config.ComponentsConfiguration
 import com.facebook.litho.config.LithoDebugConfigurations
 import com.facebook.litho.drawable.ComparableColorDrawable
 import com.facebook.litho.layout.LayoutDirection
@@ -1228,7 +1227,7 @@ open class LithoNode : Node<LithoLayoutContext>, Cloneable {
           ComponentContext.getComponentsConfig(c).shouldAddRootHostViewOrDisableBgFgOutputs &&
               (node.background != null || node.foreground != null)
       val hasAccessibilityContent =
-          ((context?.isAccessibilityEnabled == true) || ComponentsConfiguration.enableA11Y) &&
+          (context?.isAccessibilityEnabled == true) &&
               (importantForAccessibility != ViewCompat.IMPORTANT_FOR_ACCESSIBILITY_NO) &&
               (implementsAccessibility ||
                   !(nodeInfo?.contentDescription.isNullOrEmpty()) ||

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

@@ -552,7 +552,8 @@ protected void onAttached() {
     }
 
     refreshAccessibilityDelegatesIfNeeded(
-        ComponentsConfiguration.enableA11Y || isAccessibilityEnabled(getContext()));
+        ComponentsConfiguration.skipA11YValidationForKeyboard
+            || isAccessibilityEnabled(getContext()));
 
     AccessibilityManagerCompat.addAccessibilityStateChangeListener(
         mAccessibilityManager, mAccessibilityStateChangeListener);

litho-core/src/main/java/com/facebook/litho/config/ComponentsConfiguration.kt

@@ -298,9 +298,10 @@ internal constructor(
     @JvmField var useUndefinedYogaValue: Boolean = false
 
     /**
-     * This flag is used to enable A11Y support for Litho by default to measure the impact of perf.
+     * This flag is used to enable A11Y support for keyboard navigation, which was disabled due to
+     * Litho's A11Y sanity check.
      */
-    @JvmField var enableA11Y: Boolean = false
+    @JvmField var skipA11YValidationForKeyboard: Boolean = false
 
     /** This flag is used clear MovementMethod on TextInput to avoid a potential crash. */
     @JvmField var clearMovementMethod: Boolean = true