Add a provide for goog.css.common in common.css, and make common_gss an alias.
Add a provide for goog.css.common in common.css, and make common_gss an alias.

This should be a no-op change: although it removes a file from the build, that file's only purpose was to forward a second file through an artificial edge.

As a followup, I will rewrite all google3 references to `:common_gss` into `:common`, then delete the alias.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=278469711

lucidsoftware/closure-library,google/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,lucidsoftware/closure-library