[Print Preview]: Added code to support pdf fit to page functionality.

BUG=85132
TEST=none


Review URL: https://chromiumcodereview.appspot.com/10083060

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@137498 0039d316-1c4b-4281-b951-d872f2087c98
PrintMsg_Print_Params::PrintMsg_Print_Params()
  : page_size(),
    content_size(),
    printable_area(),
    margin_top(0),
    margin_left(0),
    dpi(0),
    min_shrink(0),
    max_shrink(0),
    desired_dpi(0),
    document_cookie(0),
    selection_only(false),
    supports_alpha_blend(false),
     preview_ui_addr(),
     preview_request_id(0),
     is_first_request(false),
    fit_to_paper_size(false),
     print_to_pdf(false),
     display_header_footer(false),
     date(),
    title(),
    url() {
}

PrintMsg_Print_Params::PrintMsg_Print_Params()
  : page_size(),
    content_size(),
    printable_area(),
    margin_top(0),
    margin_left(0),
    dpi(0),
    min_shrink(0),
    max_shrink(0),
    desired_dpi(0),
    document_cookie(0),
    selection_only(false),
    supports_alpha_blend(false),
     preview_ui_addr(),
     preview_request_id(0),
     is_first_request(false),
    fit_to_paper_size(true),
     print_to_pdf(false),
     display_header_footer(false),
     date(),
    title(),
    url() {
}
