public MethodId readMethodId() {
      int declaringClassIndex = readUnsignedShort();
      int protoIndex = readUnsignedShort();
      int nameIndex = readInt();
      return new MethodId(Dex.this, declaringClassIndex, protoIndex, nameIndex);
    }
Look up a descriptor index from a type index. Cheaper than: {@code
open(tableOfContents.typeIds.off + (index * SizeOf.TYPE_ID_ITEM)).readInt();}
android/android_framework/dex-maker/src/main/java/com/android/dex/Dex.java