Revert "Oilpan: Enable HeapCompaction for incremental marking"

This reverts commit 10a10dd9.

Reason for revert: Suspected for flaky crashes affecting Chromium CQ.

Original change's description:
> Oilpan: Enable HeapCompaction for incremental marking
> 
> Enables HeapCompaction for kIncrementalIdleGC and kIncrementalV8FollowupGC.
> 
> Bug: 864425
> 
> Change-Id: I1fb04d7c501a8519e106237946f86f52eb7ce8f8
> Reviewed-on: https://chromium-review.googlesource.com/c/1297782
> Reviewed-by: Kentaro Hara <haraken@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Keishi Hattori <keishi@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#603477}

TBR=haraken@chromium.org,keishi@chromium.org,mlippautz@chromium.org

Change-Id: Ie72a2eb04571945b3515ee7374a75a1ab87275c2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 864425, 899809
Reviewed-on: https://chromium-review.googlesource.com/c/1305833Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603573}

third_party/blink/renderer/platform/heap/heap_compact.cc

@@ -367,10 +367,14 @@ bool HeapCompact::ShouldCompact(ThreadHeap* heap,
     return force_compaction_gc_;
   }
 
+  // TODO(keishi): Should be enable after fixing the crashes.
+  if (marking_type == BlinkGC::kIncrementalMarking)
+    return false;
+
+  // TODO(harukamt): Add kIncrementalIdleGC and kIncrementalV8FollowupGC when we
+  // enable heap compaction for incremental marking.
   if (reason != BlinkGC::GCReason::kIdleGC &&
       reason != BlinkGC::GCReason::kPreciseGC &&
-      reason != BlinkGC::GCReason::kIncrementalIdleGC &&
-      reason != BlinkGC::GCReason::kIncrementalV8FollowupGC &&
       reason != BlinkGC::GCReason::kForcedGC)
     return false;