FLAC is used only when enable_web_speech = 1, see: src/3rdparty/chromium/content/content_browser.gypi: ... ['enable_web_speech==1', { 'dependencies': [ '../third_party/flac/flac.gyp:libflac', ], }, { # enable_web_speech==0 'sources/': [ ['exclude', '^browser/speech/'], ], }], ... WebSpeech is explicitly disabled in src/core/config/common.pri: ... # WebSpeech requires Google API keys and adds dependencies on speex and flac. GYP_CONFIG += enable_web_speech=0 ...
Thanks, fixed in git. https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=90f45d0172ad22d6b8a6e77025499156b704dcc9