More timeline cleanups

More timeline cleanups

- Blocks are associated with threads and not isolates.
- Fix isolate filters when iterating over blocks and events.
- Always add the isolateNumber argument when serializing events.
- Add new (kSerializedJSON) EventType for events already serialized to JSON.
- Have events coming from Dart code use the standard event structure w/ type = kSerializedJSON.
- Remove now unused DartTimelineEvent and machinary.
- Dart and C++ events now use the same structures and system.

R=rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/f55de246ec2bc62d34223c4046d73a8ca1d9a4d2

[Cutch, 2015-10-19 18:02:49]

Description was changed from

==========
More timeline cleanups

- Blocks are associated with threads and not isolates.
- Fix isolate filters when iterating over blocks and events.
- Always add the isolateNumber argument when serializing events.
- Add a new EventType which will be used in the next CL.
==========

to

==========
More timeline cleanups

- Blocks are associated with threads and not isolates.
- Fix isolate filters when iterating over blocks and events.
- Always add the isolateNumber argument when serializing events.
- Add new (kSerializedJSON) EventType for events already serialized to JSON.
- Have events coming from Dart code use the standard event structure w/ type =
kSerializedJSON.
- Remove now unused DartTimelineEvent and machinary.
==========

[Cutch, 2015-10-19 18:02:50]

johnmccutchan@google.com changed reviewers:
+ rmacnak@google.com

[Cutch, 2015-10-19 18:03:50]

Description was changed from

==========
More timeline cleanups

- Blocks are associated with threads and not isolates.
- Fix isolate filters when iterating over blocks and events.
- Always add the isolateNumber argument when serializing events.
- Add new (kSerializedJSON) EventType for events already serialized to JSON.
- Have events coming from Dart code use the standard event structure w/ type =
kSerializedJSON.
- Remove now unused DartTimelineEvent and machinary.
==========

to

==========
More timeline cleanups

- Blocks are associated with threads and not isolates.
- Fix isolate filters when iterating over blocks and events.
- Always add the isolateNumber argument when serializing events.
- Add new (kSerializedJSON) EventType for events already serialized to JSON.
- Have events coming from Dart code use the standard event structure w/ type =
kSerializedJSON.
- Remove now unused DartTimelineEvent and machinary.
- Dart and C++ events now use the same structures and system.
==========

[rmacnak, 2015-10-19 19:24:33]

lgtm

[Cutch, 2015-10-20 16:14:28]

Committed patchset #5 (id:80001) manually as
f55de246ec2bc62d34223c4046d73a8ca1d9a4d2 (presubmit successful).