compileEntries(mainCompilation, entries) {
    const compiler = new HtmlWebpackChildCompiler(entries);
    return compiler.compileTemplates(mainCompilation).then(
      (result) => {
        return {
          // The compiled sources to render the content
          compiledEntries: result,
          // The file dependencies to find out if a
          // recompilation is required
          dependencies: compiler.fileDependencies,
          // The main compilation hash can be used to find out
          // if this compilation was done during the current compilation
          mainCompilationHash: mainCompilation.hash,
        };
      },
      (error) => ({
        // The compiled sources to render the content
        error,
        // The file dependencies to find out if a
        // recompilation is required
        dependencies: compiler.fileDependencies,
        // The main compilation hash can be used to find out
        // if this compilation was done during the current compilation
        mainCompilationHash: mainCompilation.hash,
      }),
    );
  }
Start to compile all templates

@private
@param {Compilation} mainCompilation
@param {string[]} entries
@returns {Promise<ChildCompilationResult>}