Revert "Add tests for generator/debugger interaction"

This reverts commit r20921 for breaking the ARM/ARM64 bots.

TBR=wingo@igalia.com

Review URL: https://codereview.chromium.org/255563003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20923 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Re-enable field type tracking by default.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/258443003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20924 ce2b1a6d-e550-0410-aec6-3dcde31c8c00