not escape unicode char for import path string.

Author: ShuiRuTian

src/compiler/checker.ts

@@ -4132,7 +4132,8 @@ namespace ts {
 
             function symbolToStringWorker(writer: EmitTextWriter) {
                 const entity = builder(symbol, meaning!, enclosingDeclaration, nodeFlags)!; // TODO: GH#18217
-                const printer = createPrinter({ removeComments: true });
+                // add neverAsciiEscape for GH#39027
+                const printer = enclosingDeclaration?.kind === SyntaxKind.SourceFile ? createPrinter({ removeComments: true, neverAsciiEscape: true }) : createPrinter({ removeComments: true });
                 const sourceFile = enclosingDeclaration && getSourceFileOfNode(enclosingDeclaration);
                 printer.writeNode(EmitHint.Unspecified, entity, /*sourceFile*/ sourceFile, writer);
                 return writer;

tests/cases/fourslash/quickInfoImportNonunicodePath.ts

@@ -0,0 +1,9 @@
+/// <reference path="fourslash.ts" />
+
+// @Filename: /江南今何在/tmp.ts
+//// export const foo = 1;
+
+// @Filename: /test.ts
+//// import { foo } from "./江南/*1*/今何在/tmp";
+
+verify.quickInfoAt("1", 'module "/江南今何在/tmp"', "");