Remove transitional method MigrationCliRunner.shouldBeMigrated2

Now that `MigrationCliRunner.shouldBeMigrated` has the correct
signature and internal clients no longer use
`MigrationCliRunner.shouldBeMigrated2`, we can remove
`MigrationCliRunner.shouldBeMigrated2`.

Change-Id: I33bdc78a603c859dd8bf1928f2dbc23233ae5e7c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/178763
Reviewed-by: Samuel Rawlins <srawlins@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>

Author: stereotype441

pkg/nnbd_migration/lib/migration_cli.dart

@@ -813,25 +813,7 @@ sources' action.
   /// return additional paths that aren't inside the user's project, but doesn't
   /// override this method, then those additional paths will be analyzed but not
   /// migrated.
-  bool shouldBeMigrated(String path) => shouldBeMigrated2(path);
-
-  /// Determines whether a migrated version of the file at [path] should be
-  /// output by the migration too.  May be overridden by a derived class.
-  ///
-  /// This method should return `false` for files that are being considered by
-  /// the migration tool for information only (for example generated files, or
-  /// usages of the code-to-be-migrated by one one of its clients).
-  ///
-  /// By default returns `true` if the file is contained within the context
-  /// root.  This means that if a client overrides [computePathsToProcess] to
-  /// return additional paths that aren't inside the user's project, but doesn't
-  /// override this method, then those additional paths will be analyzed but not
-  /// migrated.
-  ///
-  /// Note: in a future version of the code, this method will be removed;
-  /// clients that are overriding this method should switch to overriding
-  /// [shouldBeMigrated] instead.
-  bool shouldBeMigrated2(String path) {
+  bool shouldBeMigrated(String path) {
     return analysisContext.contextRoot.isAnalyzed(path);
   }
 

pkg/nnbd_migration/test/migration_cli_test.dart

@@ -185,9 +185,9 @@ class _MigrationCliRunner extends MigrationCliRunner {
   }
 
   @override
-  bool shouldBeMigrated2(String path) =>
+  bool shouldBeMigrated(String path) =>
       cli._test.overrideShouldBeMigrated?.call(path) ??
-      super.shouldBeMigrated2(path);
+      super.shouldBeMigrated(path);
 
   /// Sorts the paths in [paths] for repeatability of migration tests.
   Set<String> _sortPaths(Set<String> paths) {