Properly handle absolute paths when resolving between two paths
Properly handle absolute paths when resolving between two paths

Closes https://github.com/google/closure-compiler/pull/3170.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=225057217

Yannic/closure-compiler,nawawi/closure-compiler,ChadKillingsworth/closure-compiler,Yannic/closure-compiler,vobruba-martin/closure-compiler,ChadKillingsworth/closure-compiler,vobruba-martin/closure-compiler,google/closure-compiler,ChadKillingsworth/closure-compiler,Yannic/closure-compiler,google/closure-compiler,vobruba-martin/closure-compiler,google/closure-compiler,nawawi/closure-compiler,nawawi/closure-compiler,monetate/closure-compiler,monetate/closure-compiler,google/closure-compiler,monetate/closure-compiler,vobruba-martin/closure-compiler,Yannic/closure-compiler,ChadKillingsworth/closure-compiler,monetate/closure-compiler,nawawi/closure-compiler