Bug 1384848 - Remove dead code in XPCConvert.cpp r=mrbkap

MozReview-Commit-ID: EncsNyW5Qxx

js/xpconnect/src/XPCConvert.cpp

@@ -1762,14 +1762,6 @@ XPCConvert::JSStringWithSize2Native(void* d, HandleValue s,
                     return false;
                 }
 
-                if (0 != count) {
-                    len = (count + 1) * sizeof(char16_t);
-                    if (!(*((void**)d) = moz_xmalloc(len)))
-                        return false;
-                    return true;
-                }
-
-                // else ...
                 *((const char16_t**)d) = nullptr;
                 return true;
             }