Another round of cleanups for http://www.dartbug.com/15922

runtime/vm/snapshot.cc

Index: runtime/vm/snapshot.cc
===================================================================
--- runtime/vm/snapshot.cc	(revision 32732)
+++ runtime/vm/snapshot.cc	(working copy)
@@ -117,7 +117,7 @@
   ASSERT(raw_memory != NULL);
   ASSERT(kHeaderSize == sizeof(Snapshot));
   ASSERT(kLengthIndex == length_offset());
-  ASSERT((kSnapshotFlagIndex * sizeof(int32_t)) == kind_offset());
+  ASSERT((kSnapshotFlagIndex * sizeof(int64_t)) == kind_offset());
   ASSERT((kHeapObjectTag & kInlined));
   // The kWatchedBit and kMarkBit are only set during GC operations. This
   // allows the two low bits in the header to be used for snapshotting.