Clang: Change the way completion fix-its are shown

Move the completion information to the tooltip and
show fix-it icon on the right of such item.

Change-Id: I7eff410384104387e547695171e4864760c07fb9
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/libs/utils/textutils.cpp

@@ -39,8 +39,9 @@ bool convertPosition(const QTextDocument *document, int pos, int *line, int *col
         (*column) = -1;
         return false;
     } else {
+        // line and column are both 1-based
         (*line) = block.blockNumber() + 1;
-        (*column) = pos - block.position();
+        (*column) = pos - block.position() + 1;
         return true;
     }
 }