move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/mtproto/rpc_test.go

@@ -0,0 +1,52 @@
+package mtproto
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/bin"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/mt"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/rpc"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/testutil"
+)
+
+func TestConn_dropRPC(t *testing.T) {
+	dropID := int64(10)
+
+	tests := []struct {
+		name      string
+		result    bin.Encoder
+		resultErr error
+		wantErr   bool
+	}{
+		{"Dropped", &mt.RPCAnswerDropped{MsgID: dropID}, nil, false},
+		{"DroppedRunning", &mt.RPCAnswerDroppedRunning{}, nil, false},
+		{"Unknown", &mt.RPCAnswerUnknown{}, nil, true},
+		{"Error", nil, testutil.TestError(), true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			a := assert.New(t)
+
+			client := newTestClient(func(msgID int64, seqNo int32, body bin.Encoder) (bin.Encoder, error) {
+				req, ok := body.(*mt.RPCDropAnswerRequest)
+				a.True(ok)
+				if ok {
+					a.Equal(dropID, req.ReqMsgID)
+				}
+				return tt.result, tt.resultErr
+			})
+
+			err := client.dropRPC(rpc.Request{
+				MsgID: dropID,
+				SeqNo: 1,
+			})
+			if tt.wantErr {
+				a.Error(err)
+			} else {
+				a.NoError(err)
+			}
+		})
+	}
+}