Implement field getting and setting.

This lets you use "dump" and "set <object>.<field> = <value>".

Change-Id: I47aee563b26e04f4931ac1cf3de2cd2e38db35a7
diff --git a/src/jdwp/jdwp.h b/src/jdwp/jdwp.h
index 1b766bd..f138880 100644
--- a/src/jdwp/jdwp.h
+++ b/src/jdwp/jdwp.h
@@ -55,6 +55,7 @@
 static inline ObjectId ReadObjectId(const uint8_t** pBuf) { return Read8BE(pBuf); }
 static inline RefTypeId ReadRefTypeId(const uint8_t** pBuf) { return Read8BE(pBuf); }
 static inline FrameId ReadFrameId(const uint8_t** pBuf) { return Read8BE(pBuf); }
+static inline JdwpTag ReadTag(const uint8_t** pBuf) { return static_cast<JdwpTag>(Read1(pBuf)); }
 static inline void SetFieldId(uint8_t* buf, FieldId val) { return Set4BE(buf, val); }
 static inline void SetMethodId(uint8_t* buf, MethodId val) { return Set4BE(buf, val); }
 static inline void SetObjectId(uint8_t* buf, ObjectId val) { return Set8BE(buf, val); }