Auto merge of #3307 - micbou:complete-done-allowed, r=bstaletic

[READY] Do not call OnCompleteDone on blacklisted filetypes

Fixes #3305.

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autoload/youcompleteme.vim

@@ -519,6 +519,10 @@ endfunction
 
 
 function! s:OnCompleteDone()
+  if !s:AllowedToCompleteInCurrentBuffer()
+    return
+  endif
+
   exec s:python_command "ycm_state.OnCompleteDone()"
 endfunction