Remove references to DrMemory from chromium repo.

This removes references to DrMemory for MB, GN and buildbot, and also
removes references to redundant DrMemory bots and DrMemory targets.

BUG=655521, 644217

Review-Url: https://codereview.chromium.org/2455463002
Cr-Original-Commit-Position: refs/heads/master@{#430388}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: e02ee8681a05a4e85552ec37e2a6999b0f2e76d9
1 file changed
tree: d5f1987c8f79553029c86e34071a63c93c969128
  1. tools/