[vm,aot,kernel] Fix AOT snapshot creation with kernel front-end

[vm,aot] Fix AOT snapshot creation with kernel front-end

The following problems are fixed in dart_bootstrap when it is used to
create AOT snapshot along with new kernel front-end:

* Data race between main isolate and service isolate when accessing
  vmservice_io kernel program stored in DFE::kernel_vmservice_io_.

* Double-deletion of vmservice_io kernel file program from
  VmService::LoadForGenPrecompiled / Dart_LoadLibrary /
  LoadKernelProgram and then from DFE::~DFE.

It looks like both of these bugs were introduced in
c7faf2dc6b64b65e04d677fa3ad68c1e90e19bff.

R=jensj@google.com, rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/d89b06ab096a4b574341b8873535be157e52321e

[alexmarkov, 2017-08-16 00:56:24]

Description was changed from

==========
[vm,aot] Fix AOT snapshot creation with kernel front-end

The following problems are fixed in dart_bootstrap when it is used to
create AOT snapshot along with new kernel front-end:

* Data race between main isolate and service isolate when accessing
  vmservice_io kernel program stored in DFE::kernel_vmservice_io_.

* Double-deletion of vmservice_io kernel file program from
  VmService::LoadForGenPrecompiled / Dart_LoadLibrary /
  LoadKernelProgram and then from DFE::~DFE.
==========

to

==========
[vm,aot] Fix AOT snapshot creation with kernel front-end

The following problems are fixed in dart_bootstrap when it is used to
create AOT snapshot along with new kernel front-end:

* Data race between main isolate and service isolate when accessing
  vmservice_io kernel program stored in DFE::kernel_vmservice_io_.

* Double-deletion of vmservice_io kernel file program from
  VmService::LoadForGenPrecompiled / Dart_LoadLibrary /
  LoadKernelProgram and then from DFE::~DFE.

It looks like both of these bugs were introduced in
c7faf2dc6b64b65e04d677fa3ad68c1e90e19bff.
==========

[alexmarkov, 2017-08-16 00:58:29]

alexmarkov@google.com changed reviewers:
+ aam@google.com, asiva@google.com, jensj@google.com, kmillikin@google.com,
rmacnak@google.com

[jensj, 2017-08-16 06:26:29]

lgtm

[rmacnak, 2017-08-16 19:40:33]

lgtm

[alexmarkov, 2017-08-16 19:44:49]

Description was changed from

==========
[vm,aot] Fix AOT snapshot creation with kernel front-end

The following problems are fixed in dart_bootstrap when it is used to
create AOT snapshot along with new kernel front-end:

* Data race between main isolate and service isolate when accessing
  vmservice_io kernel program stored in DFE::kernel_vmservice_io_.

* Double-deletion of vmservice_io kernel file program from
  VmService::LoadForGenPrecompiled / Dart_LoadLibrary /
  LoadKernelProgram and then from DFE::~DFE.

It looks like both of these bugs were introduced in
c7faf2dc6b64b65e04d677fa3ad68c1e90e19bff.
==========

to

==========
[vm,aot] Fix AOT snapshot creation with kernel front-end

The following problems are fixed in dart_bootstrap when it is used to
create AOT snapshot along with new kernel front-end:

* Data race between main isolate and service isolate when accessing
  vmservice_io kernel program stored in DFE::kernel_vmservice_io_.

* Double-deletion of vmservice_io kernel file program from
  VmService::LoadForGenPrecompiled / Dart_LoadLibrary /
  LoadKernelProgram and then from DFE::~DFE.

It looks like both of these bugs were introduced in
c7faf2dc6b64b65e04d677fa3ad68c1e90e19bff.

R=jensj@google.com, rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/d89b06ab096a4b574341b8873535be157e52321e
==========

[alexmarkov, 2017-08-16 19:44:50]

Committed patchset #1 (id:1) manually as
d89b06ab096a4b574341b8873535be157e52321e (presubmit successful).