For #19739 - Adds start tabsTray with multiSelect support

app/src/main/java/org/mozilla/fenix/tabstray/TabsTrayFragment.kt

@@ -261,6 +261,10 @@ class TabsTrayFragment : AppCompatDialogFragment() {
             owner = this,
             view = view
         )
+
+        if (requireArguments().getBoolean(EXTRA_MULTI_SELECT)) {
+            tabsTrayStore.dispatch(TabsTrayAction.EnterSelectMode)
+        }
     }
 
     override fun onConfigurationChanged(newConfig: Configuration) {
@@ -402,6 +406,8 @@ class TabsTrayFragment : AppCompatDialogFragment() {
     }
 
     companion object {
+        const val EXTRA_MULTI_SELECT = "enterMultiselect"
+
         // Minimum number of list items for which to show the tabs tray as expanded.
         const val EXPAND_AT_LIST_SIZE = 4
 

app/src/main/java/org/mozilla/fenix/tabstray/browser/SelectionBannerBinding.kt

@@ -15,7 +15,6 @@ import kotlinx.android.synthetic.main.tabstray_multiselect_items.view.*
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.collect
-import kotlinx.coroutines.flow.drop
 import kotlinx.coroutines.flow.map
 import mozilla.components.lib.state.helpers.AbstractBinding
 import mozilla.components.support.ktx.kotlinx.coroutines.flow.ifChanged
@@ -70,8 +69,6 @@ class SelectionBannerBinding(
 
     override suspend fun onState(flow: Flow<TabsTrayState>) {
         flow.map { it.mode }
-            // ignore initial mode update; we never start in select mode.
-            .drop(1)
             .ifChanged()
             .collect { mode ->
                 val isSelectMode = mode is Select