remove detection variables, always enable them

autoload/airline.vim

@@ -87,7 +87,7 @@ function! airline#update_statusline(active)
 
   let sl = l:mode_color
   let sl.= a:active
-        \ ? '%{airline#update_highlight()} '.s:get_section('a').' %{g:airline_paste_detection && &paste ? g:airline_paste_symbol." " : ""}'
+        \ ? '%{airline#update_highlight()} '.s:get_section('a').' %{&paste ? g:airline_paste_symbol." " : ""}'
         \ : '        %#Al9#'
   let sl.=l:mode_sep_color.g:airline_left_sep.l:info_color
   let sl.=' '.s:get_section('b').' '
@@ -115,10 +115,10 @@ function! airline#update_highlight()
     let l:mode = ['normal']
   endif
 
-  if g:airline_modified_detection && &modified
+  if &modified
     call add(l:mode, 'modified')
   endif
-  if g:airline_paste_detection && &paste
+  if &paste
     call add(l:mode, 'paste')
   endif
 

doc/airline.txt

@@ -40,10 +40,6 @@ values):
   let g:airline_right_sep='<'
 <
 
-* enable/disable color change when buffer is modified
->
-  let g:airline_modified_detection=1
-<
 
 * enable/disable fugitive integration
 >

plugin/airline.vim

@@ -18,8 +18,6 @@ call s:check_defined('g:airline_readonly_symbol', exists('g:airline_powerline_fo
 call s:check_defined('g:airline_linecolumn_prefix', exists('g:airline_powerline_fonts')?' ':':')
 call s:check_defined('g:airline_paste_symbol', 'PASTE')
 call s:check_defined('g:airline_theme', 'dark')
-call s:check_defined('g:airline_modified_detection', 1)
-call s:check_defined('g:airline_paste_detection', 1)
 call s:check_defined('g:airline_exclude_filenames', ['DebuggerWatch','DebuggerStack','DebuggerStatus'])
 call s:check_defined('g:airline_exclude_filetypes', ['netrw','diff','undotree','gundo','nerdtree','tagbar'])