Remove parallel marking support.

src/mark-compact.cc

Index: src/mark-compact.cc
diff --git a/src/mark-compact.cc b/src/mark-compact.cc
index 263de4878fcbc83661a57d70183df2166b04860a..ca079deb70900eb1725d68893f4f092967d3a736 100644
--- a/src/mark-compact.cc
+++ b/src/mark-compact.cc
@@ -38,7 +38,6 @@
 #include "ic-inl.h"
 #include "incremental-marking.h"
 #include "mark-compact.h"
-#include "marking-thread.h"
 #include "objects-visiting.h"
 #include "objects-visiting-inl.h"
 #include "stub-cache.h"
@@ -601,20 +600,6 @@ bool MarkCompactCollector::IsConcurrentSweepingInProgress() {
 }
 
 
-void MarkCompactCollector::MarkInParallel() {
-  for (int i = 0; i < FLAG_marking_threads; i++) {
-    isolate()->marking_threads()[i]->StartMarking();
-  }
-}
-
-
-void MarkCompactCollector::WaitUntilMarkingCompleted() {
-  for (int i = 0; i < FLAG_marking_threads; i++) {
-    isolate()->marking_threads()[i]->WaitForMarkingThread();
-  }
-}
-
-
 bool Marking::TransferMark(Address old_start, Address new_start) {
   // This is only used when resizing an object.
   ASSERT(MemoryChunk::FromAddress(old_start) ==