code: public ConstantInfo addConstant(ConstantInfo constant) {
          ConstantInfo info = (ConstantInfo)mConstants.get(constant);
          if (info != null) {
              return info;
          }
          
          int entryCount = constant.getEntryCount();
  
          if (mIndexedConstants != null && mPreserveOrder) {
              int size = mIndexedConstants.size();
              mIndexedConstants.setSize(size + entryCount);
              mIndexedConstants.set(size, constant);
          }
  
          mConstants.put(constant, constant);
          mEntries += entryCount;
  
          return constant;
      }
docs: Will only insert into the pool if the constant is not already in the
  pool.
  
  @return The actual constant in the pool.