Fix undefined variables

close #201

autoload/EasyMotion/cmigemo.vim

@@ -98,7 +98,7 @@ function! EasyMotion#cmigemo#getMigemoPattern(input) "{{{
         return EasyMotion#cmigemo#system('cmigemo -v -w "'.a:input.'" -d "'.s:migemodict.'"')
     else
         " Not supported
-        return input
+        return a:input
     endif
 endfunction "}}}
 

autoload/EasyMotion/helper.vim

@@ -152,7 +152,7 @@ if exists('*strchars')
     endfunction
 else
     function! EasyMotion#helper#strchars(str)
-        return strlen(substitute(str, ".", "x", "g"))
+        return strlen(substitute(a:str, ".", "x", "g"))
     endfunction
 endif "}}}
 function! EasyMotion#helper#include_multibyte_char(str) "{{{