Remove google.golang.org/grpc/codes dependency from API by adding an equivalent codes package (#1046)

* Add otel/codes package to replace google.golang.org/grpc/codes

* Replace google.golang.org/grpc/codes with otel/codes

* Update opentracing bridge to use OTel codes

* Update semconv to use OTel codes

* Update SDK to convert from OTel codes to gRPC

* go mod tidy

* Add change to CHANGELOG

* Fix word from feedback

sdk/internal/codes.go

@@ -0,0 +1,49 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal
+
+import (
+	grpccodes "google.golang.org/grpc/codes"
+
+	otelcodes "go.opentelemetry.io/otel/codes"
+)
+
+// conversions are the equivalence mapping from OpenTelemetry to gRPC codes.
+// Even though the underlying value should be the same all mappings are
+// explicit here to avoid any error.
+var conversions = map[otelcodes.Code]grpccodes.Code{
+	otelcodes.OK:                 grpccodes.OK,
+	otelcodes.Canceled:           grpccodes.Canceled,
+	otelcodes.Unknown:            grpccodes.Unknown,
+	otelcodes.InvalidArgument:    grpccodes.InvalidArgument,
+	otelcodes.DeadlineExceeded:   grpccodes.DeadlineExceeded,
+	otelcodes.NotFound:           grpccodes.NotFound,
+	otelcodes.AlreadyExists:      grpccodes.AlreadyExists,
+	otelcodes.PermissionDenied:   grpccodes.PermissionDenied,
+	otelcodes.ResourceExhausted:  grpccodes.ResourceExhausted,
+	otelcodes.FailedPrecondition: grpccodes.FailedPrecondition,
+	otelcodes.Aborted:            grpccodes.Aborted,
+	otelcodes.OutOfRange:         grpccodes.OutOfRange,
+	otelcodes.Unimplemented:      grpccodes.Unimplemented,
+	otelcodes.Internal:           grpccodes.Internal,
+	otelcodes.Unavailable:        grpccodes.Unavailable,
+	otelcodes.DataLoss:           grpccodes.DataLoss,
+	otelcodes.Unauthenticated:    grpccodes.Unauthenticated,
+}
+
+// ConvertCode converts an OpenTelemetry Code into the equivalent gRPC code.
+func ConvertCode(code otelcodes.Code) grpccodes.Code {
+	return conversions[code]
+}