Only build apidoc in release mode.

dart/tools/build.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 #
 
 import optparse
 import os
 import shutil
@@ skipping 304 matching lines @@
   else:
     target = args[0]
 
   filter_xcodebuild_output = False
   # Remember path
   old_path = os.environ['PATH']
   # Build the targets for each requested configuration.
   for target_os in options.os:
     for mode in options.mode:
       for arch in options.arch:
+        os.environ['DART_BUILD_MODE'] = mode
         build_config = utils.GetBuildConf(mode, arch)
         if HOST_OS == 'macos':
           filter_xcodebuild_output = True
           project_file = 'dart.xcodeproj'
           if os.path.exists('dart-%s.gyp' % CurrentDirectoryBaseName()):
             project_file = 'dart-%s.xcodeproj' % CurrentDirectoryBaseName()
           args = ['xcodebuild',
                   '-project',
                   project_file,
                   '-target',
@@ skipping 70 matching lines @@
         process.wait()
         if process.returncode != 0:
           print "BUILD FAILED"
           return 1
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(Main())