[LUCI] Remove Android Webview M in milo.

Bug: 838692
Change-Id: Ie253322a5d3b76ad63e8d5d6819fdd5ef8db887f
Reviewed-on: https://chromium-review.googlesource.com/1038645
Commit-Queue: Zhiling Huang <hzl@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555317}

infra/config/global/luci-milo.cfg

@@ -1650,11 +1650,6 @@ consoles: {
     category: "android|builder|arm|tester|32"
     short_name: "ci"
   }
-  builders: {
-    name: "buildbot/chromium.android/Android WebView M (dbg)"
-    category: "android|builder|arm|tester|32"
-    short_name: "bb"
-  }
   builders: {
     name: "buildbucket/luci.chromium.ci/KitKat Phone Tester (dbg)"
     category: "android|builder|arm|tester|32"
@@ -1922,7 +1917,6 @@ consoles: {
     short_name: "L"
   }
   builders: {
-    name: "buildbot/chromium.android/Android WebView M (dbg)"
     name: "buildbucket/luci.chromium.ci/Android WebView M (dbg)"
     category: "webview"
     short_name: "M"