[tools/perf] Remove top_10_mobile_memory[_ignition] benchmark.

This has now been replaced by the v8.browsing benchmark.

BUG=v8:4280,v8:5019
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.perf:android_s5_perf_cq;master.tryserver.chromium.perf:linux_perf_cq;master.tryserver.chromium.perf:mac_retina_perf_cq;master.tryserver.chromium.perf:winx64_10_perf_cq

Review-Url: https://codereview.chromium.org/2313723002
Cr-Commit-Position: refs/heads/master@{#416926}
1 file changed