Jump to line broken in the debugger

[kenzieschmoll]

When selecting a breakpoint or a stack frame when paused in the debugger, the source view does not jump to the proper line. In some cases, it jumps incorrectly to the bottom of the file, and in other cases it doesn't jump at all.

@elliette

[elliette]

Thanks! This might be fixed with dart-lang/webdev#1560, will check