Cherry-pick PR #38377 into release-3.9 (#38386)

Component commits:
4baff1b241 moveToNewFile: handle namespace imports too
Fixes #35591

Co-authored-by: Eli Barzilay <eli@barzilay.org>

src/services/refactors/moveToNewFile.ts

@@ -533,6 +533,7 @@ namespace ts.refactor {
             case SyntaxKind.ImportEqualsDeclaration:
             case SyntaxKind.ImportSpecifier:
             case SyntaxKind.ImportClause:
+            case SyntaxKind.NamespaceImport:
                 return true;
             case SyntaxKind.VariableDeclaration:
                 return isVariableDeclarationInImport(decl as VariableDeclaration);

tests/cases/fourslash/moveToNewFile_moveNamedImport.ts

@@ -0,0 +1,18 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /a.ts
+////import { foo as oFoo } from './other';
+////[|export const x = oFoo();|]
+////export const a = 0;
+
+verify.moveToNewFile({
+    newFileContents: {
+"/a.ts":
+`export const a = 0;`,
+
+"/x.ts":
+`import { foo as oFoo } from './other';
+export const x = oFoo();
+`
+    },
+});

tests/cases/fourslash/moveToNewFile_moveNamespaceImport.ts

@@ -0,0 +1,18 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /a.ts
+////import * as o from './other';
+////[|export const x = o.foo();|]
+////export const a = 0;
+
+verify.moveToNewFile({
+    newFileContents: {
+"/a.ts":
+`export const a = 0;`,
+
+"/x.ts":
+`import * as o from './other';
+export const x = o.foo();
+`
+    },
+});