refactor(@angular-devkit/build-optimizer): removed deprecated/unused passes

BREAKING CHANGE
Deprecated and outdated optimization passes class fold and import tslib have been removed.

Note: This change only effects direct @angular-devkit/schematics users and not the application developers.

Author: clydin

etc/api/angular_devkit/build_optimizer/src/_golden-api.d.ts

@@ -8,10 +8,6 @@ export declare class BuildOptimizerWebpackPlugin {
 
 export default function buildOptimizerLoader(this: webpack.loader.LoaderContext, content: string, previousSourceMap: RawSourceMap): void;
 
-export declare function getFoldFileTransformer(program: ts.Program): ts.TransformerFactory<ts.SourceFile>;
-
-export declare function getImportTslibTransformer(): ts.TransformerFactory<ts.SourceFile>;
-
 export declare function getPrefixClassesTransformer(): ts.TransformerFactory<ts.SourceFile>;
 
 export declare function getPrefixFunctionsTransformer(): ts.TransformerFactory<ts.SourceFile>;

packages/angular_devkit/build_optimizer/src/index.ts

@@ -14,8 +14,6 @@ export { buildOptimizer } from './build-optimizer/build-optimizer';
 
 export { transformJavascript } from './helpers/transform-javascript';
 
-export { getFoldFileTransformer } from './transforms/class-fold';
-export { getImportTslibTransformer } from './transforms/import-tslib';
 export { getPrefixClassesTransformer } from './transforms/prefix-classes';
 export { getPrefixFunctionsTransformer } from './transforms/prefix-functions';
 export {