NaCl: Update revision in DEPS, dac9220 -> 19f11aa

This pulls in the following Native Client changes:

fd6546b: (dschuff@chromium.org) Update revision for PNaCl and x86 newlib nacl-gcc
edcd955: (mcgrathr@chromium.org) Add test for code_data_allocate after mmap PROT_EXEC,MAP_FIXED
1c07f10: (dschuff@chromium.org) Use the LLVM integrated assembler for x86-64 nacl-clang target lib builds
c162a1e: (dschuff@chromium.org) Test that invoking longjmp with an argument of 0 causes setjmp to return 1
5513033: (dschuff@chromium.org) Update revision for PNaCl
cfe4942: (jvoung@chromium.org) Add subzero nexe to the pnacl translator build (NaCl build scripts).
4d1385a: (dschuff@chromium.org) toolchain_build: Switch canonical push URL to https://chromium.googlesource.com
7b92e88: (inferno@chromium.org) Fix ASAN build failure with linking nacl_bootstrap.
ff68e26: (jvoung@chromium.org) Revert two recent nacl-gcc x86 newlib rolls and disable longjmp test.
68a738d: (shinyak@chromium.org) Avoid deadlock in build_nexe.py
99e2d42: (mseaborn@chromium.org) Cleanup: Move desc_metadata_types.h out of public/
5e7b602b: (mcgrathr@chromium.org) Fix code_data_allocate after mmap PROT_EXEC,MAP_FIXED
19f11aa: (dschuff@chromium.org) Roll PNaCl back to ab8a5c605e1502be0605783bfe477d1a3d315817

Changes: https://chromium.googlesource.com/native_client/src/native_client/+log/dac922075e8f2e020b3538133d619c02a5a0e4fa..19f11aa481261f38f2a1e9a04e41a7e12aa70e32

BUG= https://code.google.com/p/chromium/issues/detail?id=463455
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/978073002

Cr-Commit-Position: refs/heads/master@{#319179}

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': 'dac922075e8f2e020b3538133d619c02a5a0e4fa',
+  'nacl_revision': '19f11aa481261f38f2a1e9a04e41a7e12aa70e32',
 }
 
 # Only these hosts are allowed for dependencies in this DEPS file.