Revert "Disabling wasm/WasmTanks benchmark on webview due to crashes"

This reverts commit af0c9396.

The underlying problem was that disables without an associated reason
weren't having any effect. I already had a fix for this in the most
recent build, so this additional disable shouldn't be necessary.

TBR=oysteine@chromium.org, aseemgarg@chromium.org, nednguyen@google.com
NOTRY=true

Bug: 796547
Change-Id: Idfc6e3b90619d54630125753ea76abb2dfa939ee
Reviewed-on: https://chromium-review.googlesource.com/836948
Commit-Queue: Charlie Andrews <charliea@chromium.org>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#525335}

tools/perf/expectations.config

@@ -338,7 +338,6 @@ crbug.com/664318 [ Win ] v8.runtime_stats.top_25/* [ Skip ]
 
 # Benchmark: wasm
 [ Android ] wasm/WasmTanks [ Skip ]
-crbug.com/796547 [ Android_Webview ] wasm/WasmTanks [ Skip ]
 
 ##### Perf FYI benchmarks go after here #####
 # Benchmark: loading.desktop.network_service