Roll recipe dependencies (trivial).

This is an automated CL created by the recipe roller. This CL rolls recipe
changes from upstream projects (e.g. depot_tools) into downstream projects
(e.g. tools/build).

More info is at https://goo.gl/zkKdpD. Use https://goo.gl/noib3a to file a bug
(or complain)

build:
  https://crrev.com/ea6e64ff66be6e8f658595d4d0c4f6aacc940d4b WebRTC: Make sure we test rtc_include_tests=false as well. (kjellander@chromium.org)
  https://crrev.com/73ebb69974d1d0f2f979da0e6a129100a83d2a78 WebRTC: Add cleanup_symlinks step on all bots. (kjellander@chromium.org)

TBR=martiniss@chromium.org,phajdan.jr@chromium.org

Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Review-Url: https://codereview.chromium.org/2487063006
Cr-Commit-Position: refs/heads/master@{#431238}

infra/config/recipes.cfg

@@ -5,7 +5,7 @@ deps {
   project_id: "build"
   url: "https://chromium.googlesource.com/chromium/tools/build.git"
   branch: "master"
-  revision: "e506cb3b37b72ec3e696eddf27ec514b069c80a2"
+  revision: "73ebb69974d1d0f2f979da0e6a129100a83d2a78"
 }
 deps {
   project_id: "depot_tools"