Revert of [heap] Do not invoke GC to make heap iterable.

src/log.cc

Index: src/log.cc
diff --git a/src/log.cc b/src/log.cc
index 49fd10ae581e5335622479ea7050ada08ff88faf..886ddedd6ed491ecf67b9e3fc5579fba3fafe446 100644
--- a/src/log.cc
+++ b/src/log.cc
@@ -1565,6 +1565,8 @@
 
 void Logger::LogCodeObjects() {
   Heap* heap = isolate_->heap();
+  heap->CollectAllGarbage(Heap::kMakeHeapIterableMask,
+                          "Logger::LogCodeObjects");
   HeapIterator iterator(heap);
   DisallowHeapAllocation no_gc;
   for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) {
@@ -1648,12 +1650,13 @@
 
 void Logger::LogCompiledFunctions() {
   Heap* heap = isolate_->heap();
+  heap->CollectAllGarbage(Heap::kMakeHeapIterableMask,
+                          "Logger::LogCompiledFunctions");
   HandleScope scope(isolate_);
-  int compiled_funcs_count = EnumerateCompiledFunctions(heap, NULL, NULL);
+  const int compiled_funcs_count = EnumerateCompiledFunctions(heap, NULL, NULL);
   ScopedVector< Handle<SharedFunctionInfo> > sfis(compiled_funcs_count);
   ScopedVector<Handle<AbstractCode> > code_objects(compiled_funcs_count);
-  compiled_funcs_count =
-      EnumerateCompiledFunctions(heap, sfis.start(), code_objects.start());
+  EnumerateCompiledFunctions(heap, sfis.start(), code_objects.start());
 
   // During iteration, there can be heap allocation due to
   // GetScriptLineNumber call.
@@ -1667,6 +1670,8 @@
 
 void Logger::LogAccessorCallbacks() {
   Heap* heap = isolate_->heap();
+  heap->CollectAllGarbage(Heap::kMakeHeapIterableMask,
+                          "Logger::LogAccessorCallbacks");
   HeapIterator iterator(heap);
   DisallowHeapAllocation no_gc;
   for (HeapObject* obj = iterator.next(); obj != NULL; obj = iterator.next()) {