Promote linux-libfuzzer-asan-rel trybot to full CQ blocker.

Cycle time looks good. (Caps out at about 30min for analyze exclusions.)
Flake rate looks like it's pretty much 0.

Though the bot is currently red due to a broken webrtc roll (that this
bot would have caught). Need to wait on reverting that before this can
land.

Bug: 646404
Change-Id: I26ddec32ad1b90165068c0c17946c2ac6cdc330b
Reviewed-on: https://chromium-review.googlesource.com/1229076Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592138}

infra/config/branch/cq.cfg

@@ -76,11 +76,7 @@ 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: 100
-      }
+      builders { name: "linux-libfuzzer-asan-rel" }
       builders { name: "linux-ozone-rel" }
       builders { name: "linux_chromium_compile_dbg_ng" }
       builders { name: "linux_chromium_asan_rel_ng" }