NaCl: Update revision in DEPS, r6447 -> r6459

NaCl: Update revision in DEPS, r6447 -> r6459

This pulls in the following Native Client changes:

r6448: (dschuff) Optionally build llc and lli using nacl-gcc
r6449: (mseaborn) x86-64 Windows exception patch: Fix to use the correct patch sequence size
r6450: (dschuff) Fix bit name in naclsdk.py
r6451: (bbudge) Modify sel_memory functions to support pre-reserved sandbox memory on 32 bit
r6452: (bradnelson) Adding --nacl-newlib-only option to download toolchains to allow just newlib
r6453: (halyavin) Extend IRT with nacl_irt_resource_open interface.
r6454: (khim) bce41 Remove temporary DSO hack. Use open-resource call.
r6455: (bradnelson) Switch method use to check for toolchain revision so that it works on python2.5
r6458: (mseaborn) x86-64 Windows: Use a more correct assembly-code TLS access sequence
r6459: (halyavin) Updating dynamic library test for DSO

BUG=none
TEST=nacl_integration


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=97209

[Mark Seaborn, 2011-08-17 18:57:51]

Today's DEPS update, earlier at Brad N's request.

[bradn, 2011-08-17 19:08:42]

LGTM

[commit-bot: I haz the power, 2011-08-17 21:18:42]

Change committed as 97209