Fix atomic ops on ARM to compile in NaCl untrusted targets.

base/atomicops.h

Index: base/atomicops.h
===================================================================
--- base/atomicops.h	(revision 152459)
+++ base/atomicops.h	(working copy)
@@ -132,10 +132,11 @@
 #include "base/atomicops_internals_x86_msvc.h"
 #elif defined(OS_MACOSX)
 #include "base/atomicops_internals_mac.h"
+#elif (defined(COMPILER_GCC) && defined(ARCH_CPU_ARM_FAMILY)) || \
+       defined(OS_NACL)
+#include "base/atomicops_internals_gcc.h"

[bbudge, 2012/08/21 21:49:03]

Moving this ahead of GCC x86 and adding OS_NACL so NaCl will use intrinsics by
default. This is more robust than using platform specific internals since we
would expect it to always produce valid NaCl code.

 #elif defined(COMPILER_GCC) && defined(ARCH_CPU_X86_FAMILY)
 #include "base/atomicops_internals_x86_gcc.h"
-#elif defined(COMPILER_GCC) && defined(ARCH_CPU_ARM_FAMILY)
-#include "base/atomicops_internals_arm_gcc.h"
 #elif defined(COMPILER_GCC) && defined(ARCH_CPU_MIPS_FAMILY)
 #include "base/atomicops_internals_mips_gcc.h"
 #else