Fix suppression of doubletap-to-jump-backwards-at-start.html

The test is leaking. Not sure if it's also failing, so removing the
suppression from 64d6e9f9

Bug: 996235
Change-Id: Ie1e5d11dbc7225e47fff3a6c0e62be5b193bdcd7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1764492Reviewed-by: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#689178}

third_party/blink/web_tests/LeakExpectations

@@ -98,6 +98,7 @@ crbug.com/951453 [ Linux ] external/wpt/html/user-activation/activation-transfer
 
 # Sheriff 2019-08-21
 crbug.com/996235 [ Linux ] media/controls/doubletap-to-jump-backwards-at-start.html [ Pass Leak ]
+crbug.com/996235 [ Linux ] virtual/audio-service/media/controls/doubletap-to-jump-backwards-at-start.html [ Pass Leak ]
 
 ###########################################################################
 # WARNING: Memory leaks must be fixed asap. Sheriff is expected to revert #

third_party/blink/web_tests/TestExpectations

@@ -5349,7 +5349,6 @@ crbug.com/831720 [ Win ] media/controls/tap-to-hide-controls.html [ Pass Failure
 crbug.com/831720 [ Linux ] media/controls/tap-to-hide-controls.html [ Pass Failure ]
 crbug.com/831720 [ Win ] virtual/audio-service/media/controls/doubletap-to-jump-forwards-too-short.html [ Pass Failure ]
 crbug.com/831720 [ Linux ] virtual/audio-service/media/controls/doubletap-to-jump-forwards-too-short.html [ Pass Failure ]
-crbug.com/831720 [ Linux ] virtual/audio-service/media/controls/doubletap-to-jump-backwards-at-start.html [ Pass Failure ]
 crbug.com/831720 [ Mac ] virtual/audio-service/media/controls/tap-to-hide-controls.html [ Pass Failure ]
 crbug.com/831720 [ Win ] virtual/audio-service/media/controls/tap-to-hide-controls.html [ Pass Failure ]
 crbug.com/831720 [ Linux ] virtual/audio-service/media/controls/tap-to-hide-controls.html [ Pass Failure ]