Pr 9039 (#9187)

* MM-11065: Allow to search and get archived channels from the API

* Fixing more tests

* Add some unit tests

* Add includeDeleted parameter to session permissions check function

* More test fixing

* Adding archive channels list in channels search

* Add restriction for archived channel edition

* Reverting permissions checks modification

* Changed the query parameter to include_deleted

* Enable search archive channels as true by default

* Adding tests for verify search on deleted channels

* Allowing to override archive channels during the imports

* Fixed test

* Search in archive channels from the API must be explicitly requested

* Removing includeDeleted parameter from GetChannelByName and GetChannelByNameForTeam

* Back to ViewArchivedChannels config

* Fixing tests

* Reverting GetChannelByName parameter

* Add include deleted parameter on GetChannel functions in plugins api

* Fixing tests

api4/post_test.go

@@ -1288,6 +1288,10 @@ func TestSearchPosts(t *testing.T) {
 	message = "hashtag for post4"
 	_ = th.CreateMessagePost(message)
 
+	archivedChannel := th.CreatePublicChannel()
+	_ = th.CreateMessagePostWithClient(th.Client, archivedChannel, "#hashtag for post3")
+	th.Client.DeleteChannel(archivedChannel.Id)
+
 	posts, resp := Client.SearchPosts(th.BasicTeam.Id, "search", false)
 	CheckNoError(t, resp)
 	if len(posts.Order) != 3 {
@@ -1306,6 +1310,12 @@ func TestSearchPosts(t *testing.T) {
 		t.Fatal("wrong search")
 	}
 
+	posts, resp = Client.SearchPostsIncludeDeletedChannels(th.BasicTeam.Id, "#hashtag", false)
+	CheckNoError(t, resp)
+	if len(posts.Order) != 2 {
+		t.Fatal("wrong search")
+	}
+
 	if posts, resp = Client.SearchPosts(th.BasicTeam.Id, "*", false); len(posts.Order) != 0 {
 		t.Fatal("searching for just * shouldn't return any results")
 	}
@@ -1328,7 +1338,6 @@ func TestSearchPosts(t *testing.T) {
 	Client.Logout()
 	_, resp = Client.SearchPosts(th.BasicTeam.Id, "#sgtitlereview", false)
 	CheckUnauthorizedStatus(t, resp)
-
 }
 
 func TestSearchHashtagPosts(t *testing.T) {