Revert of Disable blink_perf.canvas on linux. (patchset #1 id:1 of...

Revert of Disable blink_perf.canvas on linux. (patchset #1 id:1 of https://codereview.chromium.org/1129383007/)

Reason for revert:
Possible fix has landed, reverting to see if bot goes green.

Original issue's description:
> Disable blink_perf.canvas on linux.
>
> This has been red going on a week now.
>
> BUG=488059
> CQ_EXTRA_TRYBOTS=tryserver.chromium.perf:linux_perf_bisect;tryserver.chromium.perf:mac_perf_bisect;tryserver.chromium.perf:win_perf_bisect;tryserver.chromium.perf:android_nexus5_perf_bisect
>
> Committed: https://crrev.com/2e2d7141b8f141bfb194427afde9fb2bf1ed5486
> Cr-Commit-Position: refs/heads/master@{#330085}

TBR=sullivan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=488059

Review URL: https://codereview.chromium.org/1142643002

Cr-Commit-Position: refs/heads/master@{#330086}

tools/perf/benchmarks/blink_perf.py

@@ -167,8 +167,7 @@ class BlinkPerfCSS(benchmark.Benchmark):
     return CreatePageSetFromPath(path, SKIPPED_FILE)
 
 
-@benchmark.Disabled('win',   # crbug.com/455796
-                    'linux') # crbug.com/488059
+@benchmark.Disabled('win')  # crbug.com/455796
 class BlinkPerfCanvas(benchmark.Benchmark):
   tag = 'canvas'
   test = _BlinkPerfMeasurement