[heap] Remove left-over compaction spaces

Bug: 
Change-Id: Idc0bbc55713a6e6dcc88db77477bfddf3bd80a02
Reviewed-on: https://chromium-review.googlesource.com/781769Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49550}

src/heap/mark-compact.cc

@@ -3161,7 +3161,6 @@ class Evacuator : public Malloced {
   Evacuator(Heap* heap, RecordMigratedSlotVisitor* record_visitor)
       : heap_(heap),
         local_allocator_(heap_),
-        compaction_spaces_(heap_),
         local_pretenuring_feedback_(kInitialLocalPretenuringFeedbackCapacity),
         new_space_visitor_(heap_, &local_allocator_, record_visitor,
                            &local_pretenuring_feedback_),
@@ -3204,7 +3203,6 @@ class Evacuator : public Malloced {
 
   // Locally cached collector data.
   LocalAllocator local_allocator_;
-  CompactionSpaceCollection compaction_spaces_;
   Heap::PretenuringFeedbackMap local_pretenuring_feedback_;
 
   // Visitors for the corresponding spaces.