Change the pnacl shim from doing real shimming to just intercepting

src/untrusted/pnacl_irt_shim/nacl.scons

 # -*- python -*-
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 Import('env')
 import os
 
 # This library is part of the pnacl x86-64 toolchain only, and is used
 # to match the pnacl ABI to the IRT ABI.  It was necessitated by problems
 # in passing structures by value on x86-64.
 if not env.Bit('bitcode') or not env.Bit('target_x86_64'):
   Return()
 
-# The library must be compiled with nacl-gcc.
 # Clear out the pnacl_generate_pexe bit to allow building this as a
 # library dependency (much like the IRT).
-nacl_gcc_env = env.Clone()
-nacl_gcc_env.ClearBits('pnacl_generate_pexe')
-nacl_gcc_env = nacl_gcc_env.PNaClGetNNaClEnv()
+env.ClearBits('pnacl_generate_pexe')
 
-# Generate a 'pnacl_shim.c'
-api_glob = env.Glob('${SOURCE_ROOT}/ppapi/api/*.idl')
-api_dev_glob = env.Glob('${SOURCE_ROOT}/ppapi/api/dev/*.idl')
-generators_glob = env.Glob('${SOURCE_ROOT}/ppapi/generators/*.py')
-generated_file_c = nacl_gcc_env.Command(
-    'pnacl_shim.c',
-    (api_glob + api_dev_glob + generators_glob),
-    ('${PYTHON} ' +
-     '${SOURCE_ROOT}/ppapi/generators/generator.py ' +
-     '--srcroot=' + os.path.join('${SOURCE_ROOT}', 'ppapi', 'api') + ' ' +
-     '--wnone --pnacl --pnaclshim=${TARGETS} ' +
-     ' '.join([idl_file.abspath for idl_file in api_glob + api_dev_glob])))
-
-pnacl_irt_shim = nacl_gcc_env.ComponentLibrary('pnacl_irt_shim', [
-    generated_file_c,
+pnacl_irt_shim = env.ComponentLibrary('pnacl_irt_shim', [
     'shim_entry.c',
-    'shim_ppapi.c',
     ])
 
-# However, the library is part of the pnacl sdk (use original env).
+# The library is part of the pnacl toolchain
 env.AddLibraryToSdk(pnacl_irt_shim)
 
 env.AddObjectToSdk(['libpnacl_irt_shim.a'])