Make the build work with speech-dispatcher >= 0.8.

build/linux/system.gyp

 # Copyright (c) 2012 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.
 
 {
   'variables': {
     'conditions': [
       ['sysroot!=""', {
         'pkg-config': './pkg-config-wrapper "<(sysroot)" "<(target_arch)"',
       }, {
@@ skipping 462 matching lines @@
           }],
         ],
       },
       'hard_dependency': 1,
       'actions': [
         {
           'variables': {
             'output_h': '<(SHARED_INTERMEDIATE_DIR)/library_loaders/libspeechd.h',
             'output_cc': '<(INTERMEDIATE_DIR)/libspeechd_loader.cc',
             'generator': '../../tools/generate_library_loader/generate_library_loader.py',
+
+            # speech-dispatcher >= 0.8 ships a .pc file and installs
+            # libspeechd.h into speech-dispatcher/libspeechd.h, whereas
+            # speech-dispatcher < 0.7 does not install a .pc file and puts
+            # libspeechd.h in the top-level include directory.
+            # Take both cases into account by assuming that if the .pc file
+            # exists we have speech-dispatcher >= 0.8 and the header is in
+            # speech-dispatcher/.
+            'header_prefix': '<!(<(pkg-config) --exists speech-dispatcher && echo "speech-dispatcher/" || echo)',

[Paweł Hajdan Jr., 2013/04/16 19:23:42]

I'm not really happy about this. Auto-detection for compile-time things is sort
of fine (don't confuse with automagic dependencies which are bad,
http://www.gentoo.org/proj/en/qa/automagic.xml), but it may encourage actual
automagic dependencies in Chromium (I've seen that happen, and the pkg-config
logic was looking very similar).

Please rather use --bundled-header option for generate_library_loader.py . You
can find usage examples in this file (system.gyp).

           },
           'action_name': 'generate_libspeechd_loader',
           'inputs': [
             '<(generator)',
           ],
           'outputs': [
             '<(output_h)',
             '<(output_cc)',
           ],
           'action': ['python',
                      '<(generator)',
                      '--name', 'LibSpeechdLoader',
                      '--output-h', '<(output_h)',
                      '--output-cc', '<(output_cc)',
-                     '--header', '<libspeechd.h>',
+                     '--header', '<<(header_prefix)libspeechd.h>',
                      '--link-directly=<(linux_link_libspeechd)',
                      'spd_open',
                      'spd_say',
                      'spd_stop',
                      'spd_close',
                      'spd_set_notification_on',
                      'spd_set_voice_rate',
                      'spd_set_voice_pitch',
           ],
           'message': 'Generating libspeechd library loader.',
@@ skipping 309 matching lines @@
             ],
             'libraries': [
               '<!@(<(pkg-config) --libs-only-l libudev)',
             ],
           },
         }],
       ],
     },
   ],
 }