Remove unused $g_allow_file_cache config

Issue #33007

config_defaults_inc.php

@@ -3706,7 +3706,7 @@
 /**
  * Browser Caching Control
  * By default, we try to prevent the browser from caching anything.
- * $g_allow_browser_cache & $g_allow_file_cache will defeat this for some cases.
+ * $g_allow_browser_cache will defeat this for some cases.
  *
  * Browser Page caching - This will allow the browser to cache all pages. The
  * upside will be better performance, but there may be cases where obsolete
@@ -3718,16 +3718,6 @@
  */
 # $g_allow_browser_cache = ON;
 
-/**
- * File caching - This will allow the browser to cache downloaded files.
- * Without this set, there may be issues with IE receiving files, and launching
- * support programs.
- *
- * @todo The code that references this config considers it ON if it is set (doesn't use config_get_global() / $g_global_settings)
- * @global integer $g_allow_file_cache
- */
-# $g_allow_file_cache = ON;
-
 #################
 # Custom Fields #
 #################

core/obsolete.php

@@ -232,3 +232,6 @@
 
 # changes in 2.25.0
 config_obsolete( 'display_project_padding' );
+
+# changes in 2.27.0
+config_obsolete( 'allow_file_cache' );

docbook/Admin_Guide/en-US/config/webserver.xml

@@ -94,14 +94,6 @@ $g_custom_headers = array( 'Content-Security-Policy:' );
  					allowed) for the bug report pages.</para>
 			</listitem>
 		</varlistentry>
-		<varlistentry>
-			<term>$g_allow_file_cache</term>
-			<listitem>
-				<para>This will allow the browser to cache downloaded files.
- 					Without this set, there may be issues with IE receiving files, and launching
- 					support programs.</para>
-			</listitem>
-		</varlistentry>
 
 	</variablelist>
 </section>