Enable using the toolchain (llvm) provided FileCheck.

site_scons/site_tools/naclsdk.py

Index: site_scons/site_tools/naclsdk.py
diff --git a/site_scons/site_tools/naclsdk.py b/site_scons/site_tools/naclsdk.py
index da721f8d5d51445e69902ed5c630fb36dcfbd4f6..dfd02df4a89568a3ce39565c937bd464d8a18b72 100755
--- a/site_scons/site_tools/naclsdk.py
+++ b/site_scons/site_tools/naclsdk.py
@@ -116,6 +116,7 @@ def _SetEnvForNativeSdk(env, sdk_path):
               AR=os.path.join(bin_path, '%s-ar' % tool_prefix),
               AS=os.path.join(bin_path, '%s-as' % tool_prefix),
               ASPP=os.path.join(bin_path, '%s-%s' % (tool_prefix, cc)),
+              FILECHECK=os.path.join(bin_path, 'FileCheck'),
               GDB=os.path.join(bin_path, '%s-gdb' % tool_prefix),
               # NOTE: use g++ for linking so we can handle C AND C++.
               LINK=os.path.join(bin_path, '%s-%s' % (tool_prefix, cxx)),
@@ -193,7 +194,8 @@ def _SetEnvForPnacl(env, root):
 
   translator_root = os.path.join(os.path.dirname(root), 'pnacl_translator')
 
-  binprefix = os.path.join(root, 'bin', 'pnacl-')
+  binroot = os.path.join(root, 'bin')
+  binprefix = os.path.join(binroot, 'pnacl-')
   binext = ''
   if env.Bit('host_windows'):
     binext = '.bat'
@@ -214,6 +216,7 @@ def _SetEnvForPnacl(env, root):
 
   pnacl_ld = binprefix + 'ld' + binext
   pnacl_disass = binprefix + 'dis' + binext
+  pnacl_filecheck = os.path.join(binroot, 'FileCheck')
   pnacl_finalize = binprefix + 'finalize' + binext
   pnacl_opt = binprefix + 'opt' + binext
   pnacl_strip = binprefix + 'strip' + binext
@@ -289,6 +292,7 @@ def _SetEnvForPnacl(env, root):
               AR=pnacl_ar,
               AS=pnacl_as + ld_arch_flag,
               RANLIB=pnacl_ranlib,
+              FILECHECK=pnacl_filecheck,
               DISASS=pnacl_disass,
               OBJDUMP=pnacl_disass,
               STRIP=pnacl_strip,