Rename libchrome_zip to libzip_dart in build.

Rename libchrome_zip to libzip_dart in build.

A condition was added to the libzip target in Chromium, renaming
the output from libzip to libchrome_zip to avoid collisions
with builtin libzip.  We copied this to our libzip_dart target,
so there was a collision in the Dartium build with two products
called libchrome_zip.  Removing this lets our copy be called
libzip_dart.

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

Committed: https://github.com/dart-lang/sdk/commit/3eded1245bb36dd218b74034829e3f122eb75071

[Bill Hesse, 2016-04-12 14:32:59]

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

[Bill Hesse, 2016-04-12 14:32:59]

Tested on mac and linux.  It has always had the other name on Windows.  It was
just a mistake to copy this section in when we created it originally.

[terry, 2016-04-12 14:47:59]

terry@google.com changed reviewers:
+ terry@google.com

[terry, 2016-04-12 14:48:00]

lgtm

[Ivan Posva, 2016-04-12 21:32:09]

LGTM -ip

[Bill Hesse, 2016-04-12 22:15:41]

Description was changed from

==========
Rename libchrome_zip to libzip_dart in build.

A condition was added to the libzip target in Chromium, renaming
the output from libzip to libchrome_zip to avoid collisions
with builtin libzip.  We copied this to our libzip_dart target,
so there was a collision in the Dartium build with two products
called libchrome_zip.  Removing this lets our copy be called
libzip_dart.

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

to

==========
Rename libchrome_zip to libzip_dart in build.

A condition was added to the libzip target in Chromium, renaming
the output from libzip to libchrome_zip to avoid collisions
with builtin libzip.  We copied this to our libzip_dart target,
so there was a collision in the Dartium build with two products
called libchrome_zip.  Removing this lets our copy be called
libzip_dart.

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

Committed:
https://github.com/dart-lang/sdk/commit/3eded1245bb36dd218b74034829e3f122eb75071
==========

[Bill Hesse, 2016-04-12 22:15:43]

Committed patchset #1 (id:1) manually as
3eded1245bb36dd218b74034829e3f122eb75071 (presubmit successful).