Refactor the index model used in the save_package logic.
Refactor the index model used in the save_package logic.

This uses defined constants and array maps to do the file type logic used in the Save dialog.

This was done on top of the Randy's patch:
http://codereview.chromium.org/6334071

BUG=67135
TEST=compiles and run chrome. Everything should works as before. Save a page, notice that it should shows "Web Page, Complete" in the combobox every time you open this dialog. Changing the type in the combobox, saving the page and opening it again shouldn't change it from "Web Page, Complete". This behavior will change in the next patch.

Review URL: http://codereview.chromium.org/6246061

git-svn-id: http://src.chromium.org/svn/trunk/src@73736 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 451ed82a2612bfba0a5a0b703eed502e324b0e68
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser