[heap] Convert GCRequestType to enum class

Bug: v8:12244,v8:12245
Change-Id: I1f0c7fa26e6db208f621470d4bcbea904909a799
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3274014
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77859}

src/heap/heap.cc

@@ -1395,13 +1395,13 @@ void Heap::HandleGCRequest() {
   } else if (CollectionRequested()) {
     CheckCollectionRequested();
   } else if (incremental_marking()->request_type() ==
-             IncrementalMarking::COMPLETE_MARKING) {
+             IncrementalMarking::GCRequestType::COMPLETE_MARKING) {
     incremental_marking()->reset_request_type();
     CollectAllGarbage(current_gc_flags_,
                       GarbageCollectionReason::kFinalizeMarkingViaStackGuard,
                       current_gc_callback_flags_);
   } else if (incremental_marking()->request_type() ==
-                 IncrementalMarking::FINALIZATION &&
+                 IncrementalMarking::GCRequestType::FINALIZATION &&
              incremental_marking()->IsMarking() &&
              !incremental_marking()->finalize_marking_completed()) {
     incremental_marking()->reset_request_type();

src/heap/incremental-marking.cc

@@ -639,7 +639,7 @@ void IncrementalMarking::FinalizeMarking(CompletionAction action) {
         "[IncrementalMarking] requesting finalization of incremental "
         "marking.\n");
   }
-  request_type_ = FINALIZATION;
+  request_type_ = GCRequestType::FINALIZATION;
   if (action == GC_VIA_STACK_GUARD) {
     heap_->isolate()->stack_guard()->RequestGC();
   }
@@ -709,7 +709,7 @@ void IncrementalMarking::MarkingComplete(CompletionAction action) {
     heap()->isolate()->PrintWithTimestamp(
         "[IncrementalMarking] Complete (normal).\n");
   }
-  request_type_ = COMPLETE_MARKING;
+  request_type_ = GCRequestType::COMPLETE_MARKING;
   if (action == GC_VIA_STACK_GUARD) {
     heap_->isolate()->stack_guard()->RequestGC();
   }

src/heap/incremental-marking.h

@@ -33,7 +33,7 @@ class V8_EXPORT_PRIVATE IncrementalMarking final {
 
   enum CompletionAction { GC_VIA_STACK_GUARD, NO_GC_VIA_STACK_GUARD };
 
-  enum GCRequestType { NONE, COMPLETE_MARKING, FINALIZATION };
+  enum class GCRequestType { NONE, COMPLETE_MARKING, FINALIZATION };
 
   using MarkingState = MarkCompactCollector::MarkingState;
   using AtomicMarkingState = MarkCompactCollector::AtomicMarkingState;
@@ -123,17 +123,18 @@ class V8_EXPORT_PRIVATE IncrementalMarking final {
   inline bool IsComplete() const { return state() == COMPLETE; }
 
   inline bool IsReadyToOverApproximateWeakClosure() const {
-    return request_type_ == FINALIZATION && !finalize_marking_completed_;
+    return request_type_ == GCRequestType::FINALIZATION &&
+           !finalize_marking_completed_;
   }
 
   inline bool NeedsFinalization() {
-    return IsMarking() &&
-           (request_type_ == FINALIZATION || request_type_ == COMPLETE_MARKING);
+    return IsMarking() && (request_type_ == GCRequestType::FINALIZATION ||
+                           request_type_ == GCRequestType::COMPLETE_MARKING);
   }
 
   GCRequestType request_type() const { return request_type_; }
 
-  void reset_request_type() { request_type_ = NONE; }
+  void reset_request_type() { request_type_ = GCRequestType::NONE; }
 
   bool CanBeActivated();
 
@@ -310,7 +311,7 @@ class V8_EXPORT_PRIVATE IncrementalMarking final {
   bool finalize_marking_completed_ = false;
   IncrementalMarkingJob incremental_marking_job_;
 
-  std::atomic<GCRequestType> request_type_{NONE};
+  std::atomic<GCRequestType> request_type_{GCRequestType::NONE};
 
   Observer new_generation_observer_;
   Observer old_generation_observer_;