Support for taking full snapshots from 'dart', not just 'dart_bootstrap'.

runtime/vm/snapshot_test.cc

Index: runtime/vm/snapshot_test.cc
diff --git a/runtime/vm/snapshot_test.cc b/runtime/vm/snapshot_test.cc
index 6a028b863581ecb42c3235ede4c093127bfb62b6..e69f94cfaf05d444b00078d80c1d81da05170927 100644
--- a/runtime/vm/snapshot_test.cc
+++ b/runtime/vm/snapshot_test.cc
@@ -836,7 +836,7 @@ class TestSnapshotWriter : public SnapshotWriter {
                        &forward_list_,
                        NULL, /* test_writer */
                        true, /* can_send_any_object */
-                       true /* vm_isolate_is_symbolic */),
+                       false /* writing_vm_isolate */),
         forward_list_(thread(), kMaxPredefinedObjectIds) {
     ASSERT(buffer != NULL);
     ASSERT(alloc != NULL);
@@ -1196,8 +1196,7 @@ UNIT_TEST_CASE(FullSnapshot) {
                                 NULL,
                                 &isolate_snapshot_buffer,
                                 &malloc_allocator,
-                                NULL, /* instructions_writer */
-                                true);
+                                NULL /* instructions_writer */);
       writer.WriteFullSnapshot();
     }
   }
@@ -1257,8 +1256,7 @@ UNIT_TEST_CASE(FullSnapshot1) {
                                 NULL,
                                 &isolate_snapshot_buffer,
                                 &malloc_allocator,
-                                NULL, /* instructions_writer */
-                                true /* vm_isolate_is_symbolic */);
+                                NULL /* instructions_writer */);
       writer.WriteFullSnapshot();
     }