Fixes #77454:

- do not cary over unnecessary "extends" in tsconfig.json
- keep members ending with `Brand`, but do it at the right phase
- remove shorthand literal usage which confuses tree-shaker
- add back noImplicitAny

build/lib/standalone.js

@@ -31,6 +31,7 @@ function extractEditor(options) {
     let compilerOptions;
     if (tsConfig.extends) {
         compilerOptions = Object.assign({}, require(path.join(options.sourcesRoot, tsConfig.extends)).compilerOptions, tsConfig.compilerOptions);
+        delete tsConfig.extends;
     }
     else {
         compilerOptions = tsConfig.compilerOptions;
@@ -40,9 +41,9 @@ function extractEditor(options) {
     compilerOptions.noUnusedLocals = false;
     compilerOptions.preserveConstEnums = false;
     compilerOptions.declaration = false;
-    compilerOptions.noImplicitAny = false;
     compilerOptions.moduleResolution = ts.ModuleResolutionKind.Classic;
     options.compilerOptions = compilerOptions;
+    console.log(`Running with shakeLevel ${tss.toStringShakeLevel(options.shakeLevel)}`);
     let result = tss.shake(options);
     for (let fileName in result) {
         if (result.hasOwnProperty(fileName)) {
@@ -91,8 +92,6 @@ function extractEditor(options) {
     }
     delete tsConfig.compilerOptions.moduleResolution;
     writeOutputFile('tsconfig.json', JSON.stringify(tsConfig, null, '\t'));
-    const tsConfigBase = JSON.parse(fs.readFileSync(path.join(options.sourcesRoot, 'tsconfig.base.json')).toString());
-    writeOutputFile('tsconfig.base.json', JSON.stringify(tsConfigBase, null, '\t'));
     [
         'vs/css.build.js',
         'vs/css.d.ts',