Bug 1812859 - Update tabpreview's tab count when starting swipe

app/src/main/java/org/mozilla/fenix/browser/TabPreview.kt

@@ -13,6 +13,8 @@ import android.widget.FrameLayout
 import androidx.appcompat.content.res.AppCompatResources
 import androidx.core.view.doOnNextLayout
 import androidx.core.view.updateLayoutParams
+import mozilla.components.browser.state.selector.getNormalOrPrivateTabs
+import mozilla.components.browser.state.selector.selectedTab
 import mozilla.components.browser.thumbnails.loader.ThumbnailLoader
 import mozilla.components.concept.base.images.ImageLoadRequest
 import org.mozilla.fenix.R
@@ -50,6 +52,13 @@ class TabPreview @JvmOverloads constructor(
 
     override fun onLayout(changed: Boolean, left: Int, top: Int, right: Int, bottom: Int) {
         super.onLayout(changed, left, top, right, bottom)
+
+        val store = context.components.core.store
+        store.state.selectedTab?.let {
+            val count = store.state.getNormalOrPrivateTabs(it.content.private).size
+            binding.tabButton.setCount(count)
+        }
+
         binding.previewThumbnail.translationY = if (!context.settings().shouldUseBottomToolbar) {
             binding.fakeToolbar.height.toFloat()
         } else {