Add support for deopt mapping in the DartVM mode
In V8 mode permit function names with () in them.

This is to accomodate `(anonymous function)` names generated by V8.
Remove sort by deopts switch from the UI for now.
Improve support for perf annotate output in V8 and Dart VM modes

- fix mapping issues for V8 to have a better chance of successful association;
- after profile is loaded sort methods by the total amount of ticks (requires
verbose output from `perf annotate`);
- color blocks based on their hotness in the graph view after profile is loaded.