minijail: Switch to new cross-friendly packaging style

src/platform/minijail/SConstruct

 # -*- python -*-
 
 # Copyright (c) 2009 The Chromium OS 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 glob
 import os
 
 env = Environment()
 
 lib_sources = env.Split("""env.cc
                            interface.cc
                            minijail.cc
                            options.cc""")
 bin_sources = env.Split("""minijail_main.cc""")
 test_sources = env.Split("""minijail_unittest.cc
                             minijail_testrunner.cc""")
 benchmark_sources = glob.glob("*_microbenchmark.cc")
 
 env.Append(
     CPPPATH=['..', '../../third_party/chrome/files', '../../common'],
     CCFLAGS=['-g', '-fno-exceptions', '-Wall', '-Werror'],
     LIBPATH=['../../third_party/chrome'],
     LIBS=['cap', 'base', 'pthread', 'rt'],
 )
+for key in Split('CC CXX AR RANLIB LD NM CFLAGS CCFLAGS'):
+  value = os.environ.get(key)
+  if value != None:
+    env[key] = value
 
 env_lib = env.Clone()
 env_lib.SharedLibrary('minijail', lib_sources)
 
 env_bin = env.Clone()
 env_bin.Program('minijail', lib_sources + bin_sources)
 
 env_test = env.Clone()
 env_test.Append(LIBS=['gtest'])
 env_test.Program('minijail_unittests', lib_sources + test_sources)
 
 env_benchmarks = env.Clone()
 # Note, LIBS needs to have: 'gtest', 'base', 'rt', 'pthread'
 env_benchmarks.Append(LIBS=['microbenchmark_main.a',
                             # Since we want to run this on a prod image,
                             # we just statically pull in gtest.a.
                             File('/usr/lib/libgtest.a')],
                       LIBPATH=['../microbenchmark'])
 env_benchmarks.Program('minijail_benchmarks', benchmark_sources)