mitchellh/packer — pull request #1431 by mpage (2014-08-20 17:22:09+00:00)
Title: Allow specifying project for source images in GCE

Within GCE, images may be shared across projects. Prior to this
commit, there was no way to inform the GCE builder that a source
image belonged to a specific project. This adds an optional
'source_image_project_id' key to the GCE builder config.