PNaCl: Update subzero revision in pnacl/COMPONENT_REVISIONS
PNaCl: Update subzero revision in pnacl/COMPONENT_REVISIONS

This pulls in the following Subzero changes:

318c01b: (stichnot@chromium.org) Subzero: Fix -timing-funcs and -timing-focus flags.
263ac52: (sehr@chromium.org) Replace constant conditional branches by unconditional branches
16f8061: (eholk@chromium.org) Initial Subzero WASM prototype.
681f90f: (jpp@chromium.org) Subzero. Fixes Browser build.
0307721: (jpp@chromium.org) Subzero. Refactors Switch Lowering.
a91c341: (stichnot@chromium.org) Subzero: Improve non-MINIMAL string performance.
2b000fd: (stichnot@chromium.org) Subzero: Fix -timing-focus .
11756b5: (stichnot@chromium.org) Subzero: Dump register numbers as signed quantities.
d72385f: (stichnot@chromium.org) Subzero: Remove a couple clumsy uses of snprintf.
d12d3aa: (stichnot@chromium.org) Subzero: Fix an incorrect StringPool assert.
9a23e43: (stichnot@chromium.org) Subzero: Improve the -timing output.
e922c23: (stichnot@chromium.org) Subzero: Shorten and normalize strings in non-DUMP builds.
79568d2: (jpp@chromium.org) Subzero. ARM32. Fixes Insert/Extract v(8|16)i1 bug.
b627f09: (kschimpf@google.com) Add "vmov.<dt> <Qd>, #<imm>" to integrated ARM assembler.
3018cf2: (kschimpf@google.com) Reduce wait times for very large PEXE files.
15e77d4: (jpp@chromium.org) Subzero. ARM32. Vector shifts.
e88c7de: (jpp@chromium.org) Subzero. ARM32. Vector casts.
397f602: (jpp@chromium.org) Subzero. ARM32. Implements vector select.
67c7c41: (eholk@chromium.org) Subzero. WASM. Additional progress.
dd6dcfa: (stichnot@chromium.org) Subzero: Allow per-method controls.
085bdae: (eholk@chromium.org) Subzero, Wasm: Link and run torture tests; bug fixes.
a4d100a: (jpp@chromium.org) Subzero. ARM32. De-scalarizes icmp and fcmp for vectors.

BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4334
BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4076
BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4370
BUG= https://bugs.chromium.org/p/nativeclient/issues/detail?id=4369
TEST= PNaCl toolchain trybots

Review URL: https://codereview.chromium.org/1896003002

sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client