code: public String findLastFromMap(String key) {
          int index = mSize;
          while ((index -= 2) >= 0) {
              if (mStrings[index] == key) {
                  return mStrings[index+1];
              }
          }
          return null;
      }
docs: Specialized access method; treats vector as a Map, with 2 Strings
  per entry; first one being key, second value. Further, keys are
  assumed to be canonicalized with passed in key (ie. either intern()ed,
  or resolved from symbol table).
  Starting from the
  end (assuming even number of entries), tries to find an entry with
  matching key, and if so, returns value.