Revert of [heap] Clean up stale store buffer entries for aborted pages....

Revert of [heap] Clean up stale store buffer entries for aborted pages. (patchset #4 id:60001 of https://codereview.chromium.org/1493653002/ )

Reason for revert:
Not completely correct fix.

Original issue's description:
> [heap] Clean up stale store buffer entries for aborted pages.
>
> 1.  Let X be the aborted slot (slot in an evacuated object in an aborted page)
> 2.  Assume X contains pointer to Y and Y is in the new space, so X is in the
>     store buffer.
> 3.  Store buffer rebuilding will not filter out X (it checks InNewSpace(Y)).
> 4.  The current mark-sweep finishes. The slot X is in free space and is also in
>     the store buffer.
> 5.  A string of length 9 "abcdefghi" is allocated in the new space. The string
>     looks like |MAP|LENGTH|hgfedcba|NNNNNNNi| in memory, where NNNNNNN is
>     previous garbage. Let's assume that NNNNNNN0 was pointing to a new space
>     object before.
> 6.  Scavenge happens.
> 7.  Slot X is still in free space and in store buffer. [It causes scavenge of
>     the object Y in
>     store_buffer()->IteratePointersToNewSpace(&Scavenger::ScavengeObject). But
>     it is not important].
> 8.  Our string is promoted and is allocated over the slot X, such that NNNNNNNi
>     is written in X.
> 9.  The scavenge finishes.
> 9.  Another scavenge starts.
> 10. We crash in
>     store_buffer()->IteratePointersToNewSpace(&Scavenger::ScavengeObject) when
>     processing slot X, because it doesn't point to valid map.
>
> BUG=chromium:524425,chromium:564498
> LOG=N
> R=hpayer@chromium.org, ulan@chromium.org
>
> Committed: https://crrev.com/2e7eea4aef3403969fe885e30f892d46253b3572
> Cr-Commit-Position: refs/heads/master@{#32495}

TBR=hpayer@chromium.org,ulan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:524425,chromium:564498

Review URL: https://codereview.chromium.org/1489243004

Cr-Commit-Position: refs/heads/master@{#32504}

src/heap/mark-compact.cc

@@ -683,8 +683,6 @@ void MarkCompactCollector::CollectEvacuationCandidates(PagedSpace* space) {
   PageIterator it(space);
   while (it.has_next()) {
     Page* p = it.next();
-    // Invariant: No page should be marked as aborted after a GC.
-    DCHECK(!p->IsFlagSet(Page::COMPACTION_WAS_ABORTED));
     if (p->NeverEvacuate()) continue;
     if (p->IsFlagSet(Page::POPULAR_PAGE)) {
       // This page had slots buffer overflow on previous GC, skip it.
@@ -3280,13 +3278,8 @@ void MarkCompactCollector::EvacuatePagesInParallel() {
         //   happens upon moving (which we potentially didn't do).
         // - Leave the page in the list of pages of a space since we could not
         //   fully evacuate it.
-        // - Mark them for rescanning for store buffer entries as we otherwise
-        //   might have stale store buffer entries that become "valid" again
-        //   after reusing the memory. Note that all existing store buffer
-        //   entries of such pages are filtered before rescanning.
         DCHECK(p->IsEvacuationCandidate());
         p->SetFlag(Page::COMPACTION_WAS_ABORTED);
-        p->set_scan_on_scavenge(true);
         abandoned_pages++;
         break;
       case MemoryChunk::kCompactingFinalize:

src/heap/spaces.h

@@ -328,8 +328,7 @@ class MemoryChunk {
     PRE_FREED,
 
     // |COMPACTION_WAS_ABORTED|: Indicates that the compaction in this page
-    //   has been aborted and needs special handling, i.e., sweeper and store
-    //   buffer.
+    //   has been aborted and needs special handling by the sweeper.
     COMPACTION_WAS_ABORTED,
 
     // Last flag, keep at bottom.