Include a no-op bin/README.txt|bin/readme.txt file in the installer's

talkback package so that the installer doesn't generate a nasty -214
DOES_NOT_EXIST error if/when the Talkback client fails to be built and
included in the installer properly.  Bug 258625, attachment 173352.  Patch
by Jeff Walden.  r=chase@mozilla.org, a=asa@mozilla.org/chase@mozilla.org

browser/installer/unix/packages-static

@@ -307,6 +307,7 @@ bin/extensions/inspector@mozilla.org/defaults/preferences/inspector.js
 [abe]
 
 [talkback]
+bin/README.txt,bin/readme.txt
 bin/components/libqfaservices.so
 bin/components/qfaservices.xpt
 bin/components/talkback/*

browser/installer/windows/packages-static

@@ -293,6 +293,7 @@ bin\extensions\inspector@mozilla.org\chrome\icons\default\winInspectorMain.ico
 [abe]
 
 [talkback]
+bin\README.txt,bin\readme.txt
 bin\components\qfaservices.dll
 bin\components\qfaservices.xpt
 bin\components\BrandRes.dll