Add a comment clarifying the intent of the code that may look like a bug.

Change-Id: Idd340f939bcfbe6bb8cf2f589662ea8691e1606c

sc/source/filter/html/htmlpars.cxx

@@ -2188,6 +2188,9 @@ OUString decodeNumberFormat(const OUString& rFmt)
             }
             if (nDigitCount)
             {
+                // Hex-encoded character found. Decode it back into its
+                // original character. An example of number format with
+                // hex-encoded chars: "\0022$\0022\#\,\#\#0\.00"
                 sal_Int32 nVal = OUString(p1, nDigitCount).toInt32(16);
                 aBuf.append(static_cast<sal_Unicode>(nVal));
             }