feat: add CloudShellErrorCode.ENVIRONMENT_UNAVAILABLE enum value

PiperOrigin-RevId: 489095106

google/cloud/shell/v1/cloudshell.proto

@@ -1,4 +1,4 @@
-// Copyright 2021 Google LLC
+// Copyright 2022 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -380,6 +380,10 @@ message CloudShellErrorDetails {
     // The user has exhausted their weekly Cloud Shell quota, and Cloud Shell
     // will be disabled until the quota resets.
     QUOTA_EXCEEDED = 5;
+
+    // The Cloud Shell environment is unavailable and cannot be connected to at
+    // the moment.
+    ENVIRONMENT_UNAVAILABLE = 6;
   }
 
   // Code indicating the specific error the occurred.

google/cloud/shell/v1/cloudshell_v1.yaml

@@ -5,6 +5,7 @@ title: Cloud Shell API
 
 apis:
 - name: google.cloud.shell.v1.CloudShellService
+- name: google.longrunning.Operations
 
 types:
 - name: google.cloud.shell.v1.AddPublicKeyMetadata
@@ -30,17 +31,6 @@ backend:
   - selector: 'google.longrunning.Operations.*'
     deadline: 30.0
 
-http:
-  rules:
-  - selector: google.longrunning.Operations.ListOperations
-    get:    '/v1/{name=operations}'
-  - selector: google.longrunning.Operations.GetOperation
-    get:    '/v1/{name=operations/**}'
-  - selector: google.longrunning.Operations.DeleteOperation
-    delete: '/v1/{name=operations/**}'
-  - selector: google.longrunning.Operations.CancelOperation
-    post:   '/v1/{name=operations/**}:cancel'
-
 authentication:
   rules:
   - selector: 'google.cloud.shell.v1.CloudShellService.*'