docs: homogenize region tags (#752)

Strykrol · web-flow · commit 2b3775a02466 · 2020-12-15T23:36:06.000Z
These samples' region tags slightly differ from identical snippets in different languages. The following is the remedy:

1. Merge this PR to fix  source (keep old tag for now)
2. Fix doc code includes to represent the better region tag
3. Submit a second PR to clean-up redundant region tag wrapping
diff --git a/samples/snippets/src/main/java/com/example/spanner/SpannerSample.java b/samples/snippets/src/main/java/com/example/spanner/SpannerSample.java
@@ -1622,6 +1622,7 @@ static void createBackup(
   }
   // [END spanner_create_backup]
 
+  // [START spanner_cancel_backup_create]
   // [START spanner_cancel_create_backup]
   static void cancelCreateBackup(
       DatabaseAdminClient dbAdminClient, DatabaseId databaseId, BackupId backupId) {
@@ -1666,6 +1667,7 @@ static void cancelCreateBackup(
     }
   }
   // [END spanner_cancel_create_backup]
+  // [END spanner_cancel_backup_create]
 
   // [START spanner_list_backup_operations]
   static void listBackupOperations(InstanceAdminClient instanceAdminClient, DatabaseId databaseId) {

Original file line number	Diff line number	Diff line change
`@@ -1622,6 +1622,7 @@ static void createBackup(`
`1622`	`1622`	`}`
`1623`	`1623`	`// [END spanner_create_backup]`
`1624`	`1624`
	`1625`	`+// [START spanner_cancel_backup_create]`
`1625`	`1626`	`// [START spanner_cancel_create_backup]`
`1626`	`1627`	`static void cancelCreateBackup(`
`1627`	`1628`	`DatabaseAdminClient dbAdminClient, DatabaseId databaseId, BackupId backupId) {`
`@@ -1666,6 +1667,7 @@ static void cancelCreateBackup(`
`1666`	`1667`	`}`
`1667`	`1668`	`}`
`1668`	`1669`	`// [END spanner_cancel_create_backup]`
	`1670`	`+// [END spanner_cancel_backup_create]`
`1669`	`1671`
`1670`	`1672`	`// [START spanner_list_backup_operations]`
`1671`	`1673`	`static void listBackupOperations(InstanceAdminClient instanceAdminClient, DatabaseId databaseId) {`