[mingw-angleproject/f18] (3 commits) ...Rebuild against latest mingw-crt (fixes Windows XP compatibility issue, RHBZ #917323)

[Erik van Pienbroek]

Summary of changes:

  2f2c5bb... Another gyp b0rkedness workaround (*)
  fb8bed7... Set the environment variables before running gyp (*)
  5bd7379... Rebuild against latest mingw-crt (fixes Windows XP compatib

(*) This commit already existed in another branch; no separate mail sent