Fix unnecessary Observatory rebuilds in Flutter

Fix unnecessary Observatory rebuilds in Flutter

The cause of the rebuilds was that in v 1.14, running `pub build` modifies pubspec.lock file (v 1.13 and below did not do this, bug filed #25688) resulting in unnecessary rebuilds.

- Remove two output build rules because they cause issues with Make.
- Write our own stamp file and use that instead of pubspec.lock.

R=zra@google.com

Committed: https://github.com/dart-lang/sdk/commit/3bf51e01386a0b0d12dc6655a69b58e3f67fcf02

[Cutch, 2016-02-04 21:16:53]

Description was changed from

==========
Fix unnecessary Observatory rebuilds in Flutter

BUG=
==========

to

==========
Fix unnecessary Observatory rebuilds in Flutter

The cause of the rebuilds was that in v 1.14, running `pub build` modifies
pubspec.lock file (v 1.13 and below did not do this, bug filed #25688) resulting
in unnecessary rebuilds.

- Remove two output build rules because they cause issues with Make.
- Write our own stamp file and use that instead of pubspec.lock.
==========

[Cutch, 2016-02-04 21:16:53]

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

[zra, 2016-02-04 21:20:18]

lgtm with small fix

https://codereview.chromium.org/1664403002/diff/1/tools/observatory_tool.py
File tools/observatory_tool.py (right):

https://codereview.chromium.org/1664403002/diff/1/tools/observatory_tool.py#n...
tools/observatory_tool.py:218: if result < 0:
if result == 0:
  CreateTimeStampFile(options)
return result

[Cutch, 2016-02-04 21:23:17]

https://codereview.chromium.org/1664403002/diff/1/tools/observatory_tool.py
File tools/observatory_tool.py (right):

https://codereview.chromium.org/1664403002/diff/1/tools/observatory_tool.py#n...
tools/observatory_tool.py:218: if result < 0:
On 2016/02/04 21:20:18, zra wrote:
> if result == 0:
>   CreateTimeStampFile(options)
> return result

Done.

[Cutch, 2016-02-04 21:23:53]

Description was changed from

==========
Fix unnecessary Observatory rebuilds in Flutter

The cause of the rebuilds was that in v 1.14, running `pub build` modifies
pubspec.lock file (v 1.13 and below did not do this, bug filed #25688) resulting
in unnecessary rebuilds.

- Remove two output build rules because they cause issues with Make.
- Write our own stamp file and use that instead of pubspec.lock.
==========

to

==========
Fix unnecessary Observatory rebuilds in Flutter

The cause of the rebuilds was that in v 1.14, running `pub build` modifies
pubspec.lock file (v 1.13 and below did not do this, bug filed #25688) resulting
in unnecessary rebuilds.

- Remove two output build rules because they cause issues with Make.
- Write our own stamp file and use that instead of pubspec.lock.

R=zra@google.com

Committed:
https://github.com/dart-lang/sdk/commit/3bf51e01386a0b0d12dc6655a69b58e3f67fcf02
==========

[Cutch, 2016-02-04 21:23:55]

Committed patchset #2 (id:20001) manually as
3bf51e01386a0b0d12dc6655a69b58e3f67fcf02 (presubmit successful).