Remove hotword installation code at compile time if hotwording disabled.

chrome/chrome_browser.gypi

Index: chrome/chrome_browser.gypi
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index e5f641a7a65b32ad49ad62d7eb3acf0f25ad0a3a..29f335d0320f14f652ee70076bdd228c27242a5b 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -3582,9 +3582,6 @@
         ['enable_session_service==1', {
           'sources': [ '<@(chrome_browser_session_service_sources)' ],
         }],
-        ['enable_hotwording==1', {
-          'defines': [ 'ENABLE_HOTWORDING' ],
-        }],
         ['OS!="android" and OS!="ios" and chromeos==0', {
           'sources': [ '<@(chrome_browser_desktop_sources)' ],
         }],