Attempt to fix dartium mac build

Attempt to fix dartium mac build

Committed: https://code.google.com/p/dart/source/detail?r=12969

[ahe, 2012-09-27 15:27:57]

This is a hunch.

[ricow1, 2012-09-27 15:29:50]

LGTM, lets give it a shot

[ahe, 2012-09-27 15:57:14]

Let me try to explain what I think is going on:

Because dart/runtime/tools/gyp/runtime-configurations.gypi	is included by
dart/runtime/dart-runtime.gyp, the configurations in there are created
unconditionally. This is unlike the ones in dart/tools/gyp/configurations.gypi.
These only gets included in the Dart build using -Idart/tools/gyp/all.gypi.

The Chromium build defines different configurations. But Chromium's
configurations doesn't include all the Dart_ configurations.

I think the Ninja generator was changed and handles configurations differently,
and now assumed that Dart_x64_Base was a "concrete" configuration and it needed
to generate build files for this configuration. This leads to an error when it
tried to look up the key 'Dart_x64_Base' in another dictionary. Making
'Dart_x64_Base' an other abstract configurations abstract solves this problem.

Although this is a bug in Ninja (it shouldn't crash), this change still makes
sense: it is likely that we have been generating all the configurations
mentioned in dart/runtime/tools/gyp/runtime-configurations.gypi on the Dartium
build bots. And we shouldn't do that.

[Anton Muhin, 2012-09-28 09:58:09]

Thanks a lot, Peter.

Just for my education, where I can find any info about abstract vs. concrete
configurations?

[ahe, 2012-09-28 10:41:58]

On 2012/09/28 09:58:09, Anton Muhin wrote:
> Just for my education, where I can find any info about abstract vs. concrete
> configurations?

I'm not sure. All I know I have guessed or deducted from the sources.