Missing return for interpreter iput/get NPE.

Change-Id: I50f9fa5f6fd38af59a8fb8e8ad266f753f677a0c
diff --git a/src/interpreter/interpreter.cc b/src/interpreter/interpreter.cc
index 33d2e59..5c8ccdf 100644
--- a/src/interpreter/interpreter.cc
+++ b/src/interpreter/interpreter.cc
@@ -422,6 +422,7 @@
       obj = shadow_frame.GetReference(dec_insn.vB);
       if (UNLIKELY(obj == NULL)) {
         ThrowNullPointerExceptionForFieldAccess(f, true);
+        return;
       }
     }
     switch (field_type) {
@@ -468,6 +469,7 @@
       obj = shadow_frame.GetReference(dec_insn.vB);
       if (UNLIKELY(obj == NULL)) {
         ThrowNullPointerExceptionForFieldAccess(f, false);
+        return;
       }
     }
     switch (field_type) {