registerSourceMap method
Registers a source map for generated JavaScript sourceName.
sourceName 应与 eval/run 的 name 或模块名称一致。发生 JS 异常时,
Engine 会附加匹配的 source map,并尽量重写文件名、行列和 stack。
Implementation
void registerSourceMap(String sourceName, JsSourceMap sourceMap) {
_sourceMaps[_validateSourceName(sourceName)] = sourceMap;
}