Chunk-wise marking stack processing.

runtime/vm/thread.cc

Index: runtime/vm/thread.cc
diff --git a/runtime/vm/thread.cc b/runtime/vm/thread.cc
index aa4f67ea92a647b00488f466a0e6f9ed26af02e4..9dd0e47a9830e97f13d762e9cf1cd00a07533204 100644
--- a/runtime/vm/thread.cc
+++ b/runtime/vm/thread.cc
@@ -139,7 +139,7 @@ void Thread::EnterIsolate(Isolate* isolate) {
   isolate->set_thread_state(thread_state);
   isolate->set_vm_tag(VMTag::kVMTagId);
   ASSERT(thread->store_buffer_block_ == NULL);
-  thread->store_buffer_block_ = isolate->store_buffer()->PopBlock();
+  thread->store_buffer_block_ = isolate->store_buffer()->PopNonFullBlock();
   ASSERT(isolate->heap() != NULL);
   thread->heap_ = isolate->heap();
   thread->Schedule(isolate);
@@ -213,7 +213,7 @@ void Thread::StoreBufferBlockProcess(bool check_threshold) {
   StoreBufferBlock* block = store_buffer_block_;
   store_buffer_block_ = NULL;
   sb->PushBlock(block, check_threshold);
-  store_buffer_block_ = sb->PopBlock();
+  store_buffer_block_ = sb->PopNonFullBlock();
 }