refactor(material/legacy-snack-bar): rename ts symbols

Author: wagnermaciel

src/material/legacy-snack-bar/public-api.ts

@@ -6,10 +6,10 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-export * from './snack-bar-module';
-export * from './snack-bar';
-export * from './snack-bar-container';
-export * from './simple-snack-bar';
+export {MatLegacySnackBarModule} from './snack-bar-module';
+export {MatLegacySnackBar} from './snack-bar';
+export {MatLegacySnackBarContainer} from './snack-bar-container';
+export {LegacySimpleSnackBar} from './simple-snack-bar';
 export {
   MAT_SNACK_BAR_DATA as MAT_LEGACY_SNACK_BAR_DATA,
   MatSnackBarHorizontalPosition as MatLegacySnackBarHorizontalPosition,

src/material/legacy-snack-bar/testing/public-api.ts

@@ -6,5 +6,5 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-export * from './snack-bar-harness';
+export {MatLegacySnackBarHarness} from './snack-bar-harness';
 export {SnackBarHarnessFilters as LegacySnackBarHarnessFilters} from '@angular/material/snack-bar/testing';