Add reminder to keep section arrays in sync
diff --git a/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java b/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
index 2cffe8f..016eba2 100644
--- a/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
+++ b/dexlib2/src/main/java/org/jf/dexlib2/writer/DexWriter.java
@@ -138,6 +138,10 @@
     protected int numCodeItemItems = 0;
     protected int numClassDataItems = 0;
 
+    // The sections defined here must be kept in sync with these section arrays:
+    // - DexWriter.overflowableSections
+    // - DexPool.sections
+
     public final StringSectionType stringSection;
     public final TypeSectionType typeSection;
     public final ProtoSectionType protoSection;