handleCodeUnitLoaded(codeUnit) {
    var referrerName = codeUnit.normalizedName;
    try {
      var moduleSpecifiers = codeUnit.getModuleSpecifiers();
      codeUnit.state = PARSED;

      if (!moduleSpecifiers) {
        this.abortAll(`No module specifiers in ${referrerName}`);
        return;
      }
      codeUnit.dependencies = moduleSpecifiers.map((name) => {
        return this.getOrCreateCodeUnit_(name, referrerName, null,
            this.defaultModuleMetadata_(codeUnit.metadata));
      });
    } catch (error) {
      this.rejectOneAndAll(codeUnit, error);
      return;
    }
    codeUnit.dependencies.forEach((dependency) => {
      this.load_(dependency);
    });

    if (this.areAll(PARSED)) {
      try {
        // Currently analyze is only needed for module dependencies.
        if (codeUnit.type === 'module')
          this.analyze();
        this.transform();
        this.evaluate();
      } catch (error) {
        this.rejectOneAndAll(codeUnit, error);
      }
    }
  }
This is called when a codeUnit is loaded.
@param {CodeUnit} codeUnit