Incorrect line numbers - sourcemaps, Webpack 2 Typescript
Thats a known issue faced earlier by multiple people in the past with no resolution. Seems like chrome debugger has some open bugs regarding the similar behaviour:
https://github.com/karma-runner/karma/issues/1141
or
https://groups.google.com/forum/#!topic/google-chrome-developer-tools/n4A0WemZhHc
or
Chrome appears to report wrong line for error
I suggest in such cases, use firefox.