Remove GC prologue and epilogue callbacks.

runtime/vm/pages.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/pages.h"
 
 #include "platform/address_sanitizer.h"
 #include "platform/assert.h"
 #include "vm/compiler_stats.h"
 #include "vm/gc_marker.h"
@@ skipping 801 matching lines @@
     page = large_pages_;
     while (page != NULL) {
       if (page->type() == HeapPage::kExecutable && !page->is_image_page()) {
         page->WriteProtect(read_only);
       }
       page = page->next();
     }
   }
 }
 
-void PageSpace::MarkSweep(bool invoke_api_callbacks) {
+void PageSpace::MarkSweep() {
   Thread* thread = Thread::Current();
   Isolate* isolate = heap_->isolate();
   ASSERT(isolate == Isolate::Current());
 
   const int64_t pre_wait_for_sweepers = OS::GetCurrentMonotonicMicros();
 
   // Wait for pending tasks to complete and then account for the driver task.
   {
     MonitorLocker locker(tasks_lock());
     while (tasks() > 0) {
@@ skipping 38 matching lines @@
     SpaceUsage usage_before = GetCurrentUsage();
 
     // Mark all reachable old-gen objects.
 #if defined(PRODUCT)
     bool collect_code = FLAG_collect_code && ShouldCollectCode();
 #else
     bool collect_code = FLAG_collect_code && ShouldCollectCode() &&
                         !isolate->HasAttemptedReload();
 #endif  // !defined(PRODUCT)
     GCMarker marker(heap_);
-    marker.MarkObjects(isolate, this, invoke_api_callbacks, collect_code);
+    marker.MarkObjects(isolate, this, collect_code);
     usage_.used_in_words = marker.marked_words();
 
     int64_t mid1 = OS::GetCurrentMonotonicMicros();
 
     // Abandon the remainder of the bump allocation block.
     AbandonBumpAllocation();
     // Reset the freelists and setup sweeping.
     freelist_[HeapPage::kData].Reset();
     freelist_[HeapPage::kExecutable].Reset();
 
@@ skipping 384 matching lines @@
     return 0;
   } else {
     ASSERT(total_time >= gc_time);
     int result = static_cast<int>(
         (static_cast<double>(gc_time) / static_cast<double>(total_time)) * 100);
     return result;
   }
 }
 
 }  // namespace dart