Fix checking enough space for floating window

Author: rhysd

autoload/LanguageClient.vim

@@ -320,7 +320,8 @@ function! s:OpenHoverPreview(bufname, lines, filetype) abort
 
         " Calculate anchor
         " Prefer North, but if there is no space, fallback into South
-        if pos[1] + height <= &lines
+        let bottom_line = line('w0') + winheight() - 1
+        if pos[1] + height <= bottom_line
             let vert = 'N'
             let row = 1
         else