Make sure *BUILD* env vars are passed around for Linux official builds.

build/SConscript.main

 # Copyright (c) 2006-2008 The Chromium 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 os
 import shutil
 import sys
 
 
 if sys.platform == 'win32':
@@ skipping 448 matching lines @@
 # SCons.Environment if they exist.
 for envvar in ('CC', 'CXX', 'LINK'):
   if envvar in os.environ:
     linux_env[envvar] = os.environ[envvar]
     linux_env['ENV'][envvar] = os.environ[envvar]
 # Copy these environment variables from the outer environment to the
 # environment that the build commands run in.
 # $HOME is needed by distcc so it can find its lock file.
 for envvar in ('HOME', 'DISTCC_DIR', 'DISTCC_HOSTS', 'CCACHE_DIR',
                'INTERCEPTOR_SOCKET', 'ENFORGE_DIGEST_CACHE',
+               'CHROME_BUILD_TYPE', 'CHROMIUM_BUILD',
                'ENFORGE_CACHE_HOST', 'ENFORGE_CACHE_PORT'):
   if envvar in os.environ:
     linux_env['ENV'][envvar] = os.environ[envvar]
 
 excluded_warnings = [
   # TODO: Clean up uses of ext/hash_map and remove this.
   # (see unordered_map and base/hash_tables.h)
   '-Wno-deprecated',  # Needed for using ext/hash_map on GCC 4.3
 ]
 if not root_env.get('_GYP'):
@@ skipping 409 matching lines @@
         'all_libraries',
         'all_languages',
         'all_programs',
         'all_test_programs',
     ], projects = [p],
     COMPONENT_VS_PROJECT_SCRIPT_PATH=(
         'cd $$(ProjectDir)/$VS_PROJECT_TO_MAIN_DIR && hammer.bat'),
 )
 
 # -------------------------------------------------------------------------