Moving inspector (devtools) layout tests to within /Source/devtools provides a couple of benefits:
1. Although inspector tests use the same layout test harness as the rest of Blink, the intent of these tests are very different and aren't actually trying to test the layout. In particular, inspector tests run quite slowly (~80 seconds for 1100 tests) relative to other layout tests.
2. This enables external contributors to run and update tests by only checking out our subtree mirror: https://chromium.googlesource.com/chromium/src/third_party/WebKit/Source/devtools/
This reduces the barrier for contribution for external contributors that are working on front-end only (e.g. javascript) changes and don't need the entire Chromium repo.
Comment 1 by bugdroid1@chromium.org
, Nov 4 2016