[heap] Don't move pages in reduce memory mode

src/heap/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/mark-compact.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/base/sys-info.h"
 #include "src/code-stubs.h"
@@ skipping 3278 matching lines @@
       heap_, heap_->isolate()->cancelable_task_manager(),
       &page_parallel_job_semaphore_);
 
   int abandoned_pages = 0;
   intptr_t live_bytes = 0;
   for (Page* page : evacuation_candidates_) {
     live_bytes += page->LiveBytes();
     job.AddPage(page, &abandoned_pages);
   }
 
+  const bool reduce_memory = heap()->ShouldReduceMemory();
   for (Page* page : newspace_evacuation_candidates_) {
     live_bytes += page->LiveBytes();
-    if (!page->NeverEvacuate() &&
+    if (!reduce_memory && !page->NeverEvacuate() &&
         (page->LiveBytes() > Evacuator::PageEvacuationThreshold())) {
       if (page->InIntermediateGeneration()) {
         EvacuateNewSpacePageVisitor::MoveToOldSpace(page, heap()->old_space());
       } else {
         EvacuateNewSpacePageVisitor::MoveToToSpace(page);
       }
     }
 
     job.AddPage(page, &abandoned_pages);
   }
@@ skipping 714 matching lines @@
       // The target is always in old space, we don't have to record the slot in
       // the old-to-new remembered set.
       DCHECK(!heap()->InNewSpace(target));
       RecordRelocSlot(host, &rinfo, target);
     }
   }
 }
 
 }  // namespace internal
 }  // namespace v8