Switch to using the LLVM gold plugin as a fully linked-in object rather than DSO.

pnacl/driver/driver_env.py

 #!/usr/bin/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.
 #
 # IMPORTANT NOTE: If you make local mods to this file, you must run:
 #   %  pnacl/build.sh driver
 # in order for them to take effect in the scons build.  This command
 # updates the copy in the toolchain/ tree.
 
@@ skipping 89 matching lines @@
   'EXEC_EXT_darwin' : '',
   'EXEC_EXT_linux'  : '',
   'EXEC_EXT_windows': '.exe',
 
   'SCONS_OS'            : '${SCONS_OS_%BUILD_OS%}',
   'SCONS_OS_linux'      : 'linux',
   'SCONS_OS_darwin'     : 'mac',
   'SCONS_OS_windows'    : 'win',
 
   # Tool Pathnames
-  'GOLD_PLUGIN_SO'  : '${BASE_LLVM}/${SO_DIR}/${SO_PREFIX}LLVMgold${SO_EXT}',
   'DRAGONEGG_PLUGIN': '${BASE_GCC}/lib/dragonegg${SO_EXT}',
 
   'SCONS_STAGING'       : '${SCONS_STAGING_%ARCH%}',
   'SCONS_STAGING_X8632' : '${SCONS_OUT}/opt-${SCONS_OS}-x86-32/staging',
   'SCONS_STAGING_X8664' : '${SCONS_OUT}/opt-${SCONS_OS}-x86-64/staging',
   'SCONS_STAGING_ARM'   : '${SCONS_OUT}/opt-${SCONS_OS}-arm/staging',
 
   'SEL_UNIVERSAL_PREFIX': '${USE_EMULATOR ? ${EMULATOR}}',
   'SEL_UNIVERSAL'       : '${SCONS_STAGING}/sel_universal${EXEC_EXT}',
   # NOTE: -Q skips sel_ldr qualification tests, -c -c skips validation
@@ skipping 383 matching lines @@
       return (leftpart, i)
 
     (middlepart, j) = self.eval_bracket_expr(s, i+2, ['}'])
     if j == len(s) or s[j] != '}':
       ParseError(s, i, j, 'Unterminated ${')
 
     (rightpart, k) = self.eval_expr(s, j+1, terminators)
     return (leftpart + middlepart + rightpart, k)
 
 env = Environment()