bug 176505, sr=sfraser, r=kin. fix packaging for new xpt file

xpinstall/packager/packages-mac

@@ -99,6 +99,7 @@ viewer:Components:universalchardet.shlb
 viewer:Components:ChomeRegistry.shlb 
 viewer:Components:chrome.xpt
 viewer:Components:Composer.shlb 
+viewer:Components:composer.xpt
 viewer:Components:content.shlb
 viewer:Components:content.xpt
 viewer:Components:cookie.xpt 

xpinstall/packager/packages-unix

@@ -111,6 +111,7 @@ bin/components/libcaps.so
 bin/components/libchrome.so
 bin/components/libcookie.so
 bin/components/libcomposer.so
+bin/components/composer.xpt
 bin/components/libdocshell.so
 bin/components/libeditor.so
 bin/components/libembedcomponents.so

xpinstall/packager/packages-win

@@ -101,6 +101,7 @@ bin\components\chrome.xpt
 bin\components\cookie.dll
 bin\components\cookie.xpt
 bin\components\composer.dll
+bin\components\composer.xpt
 bin\components\docshell.dll
 bin\components\docshell_base.xpt
 bin\components\jsdom.dll