Add a version number for full and script snapshots.

Landing change from Zach for adding snapshot version numbers.
(Add a version number for full and script snapshots.
 Currently the VM version string is used for versioning. This can
 potentially be improved to use a version string that tracks the format
 of the internal VM structures.)

Committed: https://code.google.com/p/dart/source/detail?r=39612

[siva, 2014-08-25 23:26:38]

asiva@google.com changed reviewers:
+ iposva@google.com

[Ivan Posva, 2014-08-26 23:52:43]

LTGMwC

-Ivan

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:4887: ASSERT(tmp.IsError());
If this is an error we should just return the error object. Otherwise we should
create a new error object as previously.

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc
File runtime/vm/snapshot.cc (right):

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc#n...
runtime/vm/snapshot.cc:431: "Wrong full snapshot version. Found %s Expected %s",
Strange capitalization of Expected.

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc#n...
runtime/vm/snapshot.cc:485: return ReadObject();
Alternatively you could do the test for library in this function and either
return the library object or an error object.

[siva, 2014-08-27 18:25:08]

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/dart_api_impl...
runtime/vm/dart_api_impl.cc:4887: ASSERT(tmp.IsError());
On 2014/08/26 23:52:42, Ivan Posva wrote:
> If this is an error we should just return the error object. Otherwise we
should
> create a new error object as previously.


Removed this error and change ReadScriptSnapshot to return a library object or
an error object.

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc
File runtime/vm/snapshot.cc (right):

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc#n...
runtime/vm/snapshot.cc:431: "Wrong full snapshot version. Found %s Expected %s",
On 2014/08/26 23:52:43, Ivan Posva wrote:
> Strange capitalization of Expected.

Fixed.

https://codereview.chromium.org/506753003/diff/60001/runtime/vm/snapshot.cc#n...
runtime/vm/snapshot.cc:485: return ReadObject();
On 2014/08/26 23:52:43, Ivan Posva wrote:
> Alternatively you could do the test for library in this function and either
> return the library object or an error object.

Done.

[Jason Robbins -- corp, 2014-08-27 18:26:11]

On 2014/08/26 23:52:43, Ivan Posva wrote:
> LTGMwC

These don't count any more.  You need to write it as a separate word.

Thanks,
jason!

[siva, 2014-08-27 18:27:56]

Committed patchset #5 (id:80001) manually as r39612 (presubmit successful).