Fix for issue 6311 (serialize the right type).

vm/raw_object_snapshot.cc

Index: vm/raw_object_snapshot.cc
===================================================================
--- vm/raw_object_snapshot.cc	(revision 14118)
+++ vm/raw_object_snapshot.cc	(working copy)
@@ -2113,13 +2113,14 @@
 #undef EXTERNALARRAY_READ_FROM
 
 
+template<typename ElementT>
 static void ByteArrayWriteTo(SnapshotWriter* writer,
                              intptr_t object_id,
                              Snapshot::Kind kind,
                              intptr_t byte_array_kind,
                              intptr_t tags,
                              RawSmi* length,
-                             uint8_t* data) {
+                             ElementT* data) {
   ASSERT(writer != NULL);
   intptr_t len = Smi::Value(length);
 
@@ -2157,7 +2158,7 @@
                    k##name##ArrayCid,                                          \
                    writer->GetObjectTags(this),                                \
                    ptr()->length_,                                             \
-                   reinterpret_cast<uint8_t*>(ptr()->data_));                  \
+                   ptr()->data_);                                              \
 }                                                                              \
 
 
@@ -2175,7 +2176,7 @@
                    k##name##ArrayCid,                                          \
                    writer->GetObjectTags(this),                                \
                    ptr()->length_,                                             \
-                   reinterpret_cast<uint8_t*>(ptr()->external_data_->data())); \
+                   ptr()->external_data_->data());                             \
 }                                                                              \