VM: Split GYP build target 'runtime' to speedup SDK build times.

VM: Split GYP build target 'runtime' to speedup SDK build times.

This speeds up a regular full 'runtime' build on my Linux box by around 40%
by avoiding to build the precompiled runtime by default (measured user-time)
'runtime_precompiled' also builds 35% faster than 'runtime' before.

BUG=
R=iposva@google.com, rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/9ff22315d88aadc6ebfc93757f2131ecd23aa383

[Florian Schneider, 2016-04-20 14:55:06]

fschneider@google.com changed reviewers:
+ iposva@google.com, rmacnak@google.com

[Ivan Posva, 2016-04-20 21:15:48]

Please announce these changes to the VM team, so they are not surprised if a
target they expect has not been built.

LGTM

-Ivan

[rmacnak, 2016-04-20 22:39:26]

lgtm 

Bill, this will require an update of the precompilation bots' build step to

tools/build.py ... runtime_precompiled

[Florian Schneider, 2016-04-21 09:40:24]

Description was changed from

==========
VM: Split GYP build target 'runtime' to speedup SDK build times.

This speeds up a regular full 'runtime' build on my Linux box by around 40%
by avoiding to build the precompiled runtime by default (measured user-time)
'runtime_precompiled' also builds 35% faster than 'runtime' before.

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

to

==========
VM: Split GYP build target 'runtime' to speedup SDK build times.

This speeds up a regular full 'runtime' build on my Linux box by around 40%
by avoiding to build the precompiled runtime by default (measured user-time)
'runtime_precompiled' also builds 35% faster than 'runtime' before.

BUG=
R=iposva@google.com, rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/9ff22315d88aadc6ebfc93757f2131ecd23aa383
==========

[Florian Schneider, 2016-04-21 09:40:26]

Committed patchset #1 (id:1) manually as
9ff22315d88aadc6ebfc93757f2131ecd23aa383.