refactor(compiler): remove interpolation-related symbols

We removed the ability to customize the interpolation some time ago. These changes remove the remaining code related to them.

Author: crisbeto

packages/compiler/src/assertions.ts

@@ -50,7 +50,6 @@ export * from './i18n/index';
 export * from './injectable_compiler_2';
 export {publishFacade} from './jit_compiler_facade';
 export * from './ml_parser/ast';
-export {DEFAULT_INTERPOLATION_CONFIG, InterpolationConfig} from './ml_parser/defaults';
 export * from './ml_parser/html_parser';
 export * from './ml_parser/html_tags';
 export {LexerRange} from './ml_parser/lexer';