Fix bogus assert in HeapIterator.

BUG=397485
LOG=n
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/416403011

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22642 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -3302,8 +3302,7 @@ bool Heap::CanMoveObjectStart(HeapObject* object) {
   // for concurrent sweeping. The WasSwept predicate for concurrently swept
   // pages is set after sweeping all pages.
   return (!is_in_old_pointer_space && !is_in_old_data_space) ||
-         page->WasSwept() ||
-         (page->parallel_sweeping() <= MemoryChunk::SWEEPING_FINALIZE);
+         page->WasSwept() || page->SweepingCompleted();
 }
 
 

src/spaces.cc

@@ -58,7 +58,7 @@ HeapObjectIterator::HeapObjectIterator(Page* page,
              page->area_end(),
              kOnePageOnly,
              size_func);
-  ASSERT(page->WasSweptPrecisely());
+  ASSERT(page->WasSweptPrecisely() || page->SweepingCompleted());
 }
 
 

src/spaces.h

@@ -478,6 +478,8 @@ class MemoryChunk {
             SWEEPING_PENDING;
   }
 
+  bool SweepingCompleted() { return parallel_sweeping() <= SWEEPING_FINALIZE; }
+
   // Manage live byte count (count of bytes known to be live,
   // because they are marked black).
   void ResetLiveBytes() {

src/store-buffer.cc

@@ -505,9 +505,9 @@ void StoreBuffer::IteratePointersToNewSpace(ObjectSlotCallback slot_callback,
               }
             }
           } else {
-            if (page->parallel_sweeping() > MemoryChunk::SWEEPING_FINALIZE) {
+            if (!page->SweepingCompleted()) {
               heap_->mark_compact_collector()->SweepInParallel(page, owner);
-              if (page->parallel_sweeping() > MemoryChunk::SWEEPING_FINALIZE) {
+              if (!page->SweepingCompleted()) {
                 // We were not able to sweep that page, i.e., a concurrent
                 // sweeper thread currently owns this page.
                 // TODO(hpayer): This may introduce a huge pause here. We