Move delta payloads out of critical path.

BUG=chromium:422634
TEST=Run example trybot run with hwtest.

Change-Id: I531e798fc7d2d746e21fbfcf55a2be197e15120d
Reviewed-on: https://chromium-review.googlesource.com/223117
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: David James <davidjames@chromium.org>
Tested-by: David James <davidjames@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index 8540095..67b69e6 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -457,10 +457,6 @@
       builder_run: BuilderRun object for these background stages.
       board: Board name.
     """
-    # Upload HWTest artifacts first.
-    self._RunStage(artifact_stages.UploadTestArtifactsStage, board,
-                   builder_run=builder_run)
-
     parallel_stages = []
 
     # We can not run hw tests without archiving the payloads.
@@ -567,6 +563,7 @@
         [artifact_stages.DevInstallerPrebuiltsStage, board],
         [artifact_stages.DebugSymbolsStage, board],
         [artifact_stages.CPEExportStage, board],
+        [artifact_stages.UploadTestArtifactsStage, board],
     ]
 
     stage_objs = [self._GetStageInstance(*x, builder_run=builder_run)