message: refactor(compiler): pass rootDir to tsickle
  tsickle's underlying API has changed to require passing a rootDir to getGeneratedExterns.
  PR Close
diff: @@ -410,7 +410,7 @@ export function compile({
  const hasError = diagnostics.some((diag) => diag.category === ts.DiagnosticCategory.Error);
  if (!hasError) {
  if (bazelOpts.tsickleGenerateExterns) {
  - externs += tsickle.getGeneratedExterns(tsickleEmitResult.externs);
  + externs += tsickle.getGeneratedExterns(tsickleEmitResult.externs, compilerOpts.rootDir!);
  }
  if (bazelOpts.manifest) {
  const manifest = constructManifest(tsickleEmitResult.modulesManifest, bazelHost);
  