message: Remove the need to go from IRCode to DexCode by making an IRCode copy
  Summary:
  Instead of going through DexCode, make a copy of the IRCode and pass it to the
  new method.
diff: @@ -463,10 +463,7 @@ DexMethod* DexMethod::make_method_from(DexMethod* that,
  m->m_anno = new DexAnnotationSet(*that->m_anno);
  }
  - // TODO: have method cloning work for FatMethods so this sync is unnecessary
  - that->sync();
  - m->m_dex_code.reset(new DexCode(*that->m_dex_code));
  - that->balloon();
  + m->set_code(std::make_unique<IRCode>(*that->get_code()));
  m->m_access = that->m_access;
  m->m_concrete = that->m_concrete;
  @@ -477,7 +474,6 @@ DexMethod* DexMethod::make_method_from(DexMethod* that,
  m->m_param_anno.emplace(pair.first, new DexAnnotationSet(*pair.second));
  }
  - m->balloon();
  return m;
  }
  