Set linux-libfuzzer-asan-rel trybot at 10% CQ experiment.

Blocked on adding more bots to the pool: http://crrev.com/i/676080

Bug: 646404
Change-Id: I46021d3173e430287afffde7b9da77bddb6c5487
Reviewed-on: https://chromium-review.googlesource.com/1217037Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590135}

infra/config/branch/cq.cfg

@@ -71,6 +71,11 @@ verifiers {
         experiment_percentage: 10
       }
       builders { name: "linux-jumbo-rel" }
+      # TODO(crbug.com/646404): Scale this up to 100% mandatory.
+      builders {
+        name: "linux-libfuzzer-asan-rel"
+        experiment_percentage: 10
+      }
       builders { name: "linux-ozone-rel" }
       builders { name: "linux_chromium_compile_dbg_ng" }
       builders { name: "linux_chromium_asan_rel_ng" }