NaCl: Update revision in DEPS, e255676 -> bcaef62

This pulls in the following Native Client changes:

1da5d86: (sbc@chromium.org) Fix for gyp build of nacl_bootstrap with target_arch=mips
f404a83: (scottmg@chromium.org) Reland of 'vs2015: avoid redefining UINT8_MAX et al, some warning fixes'
3b1b3cf: (rickyz@chromium.org) Add SIGHUP and SIGTERM handlers in NaCl.
12ab4282: (sergiyb@chromium.org) Added CQ config to the nacl repo
ae55d9f: (bradnelson@chromium.org) Don't run asan toolchain build through runtest.py
23b1555: (jvoung@chromium.org) Update revision for PNaCl
bcaef62: (mseaborn@chromium.org) SelLdrLauncher: Allow using a subset of SetupCommand(): Make some methods public

Changes: https://chromium.googlesource.com/native_client/src/native_client/+log/e255676bce441a5a54072548cd1cf1ed8eaaecad..bcaef620a70f2e84e3660bd9098c4af811528f47

BUG=none
TEST=browser_tests and nacl_integration
CQ_EXTRA_TRYBOTS=tryserver.chromium.linux:linux_chromium_dbg_32_ng,linux_arm_compile,linux_nacl_sdk_build

Review URL: https://codereview.chromium.org/1159693005

Cr-Commit-Position: refs/heads/master@{#333172}

DEPS

@@ -94,7 +94,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling NaCl
   # and whatever else without interference from each other.
-  'nacl_revision': 'e255676bce441a5a54072548cd1cf1ed8eaaecad',
+  'nacl_revision': 'bcaef620a70f2e84e3660bd9098c4af811528f47',
 }
 
 # Only these hosts are allowed for dependencies in this DEPS file.