heap: Ephemeron processing: Remove strongification parameter

In the strongification case the callbacks should return false
indicating that the key is alive and value should be traced.

Bug: 1019191
Change-Id: I508dcb6fa90d91417788302aef1f448a8fc9a744
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1897928Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712478}

third_party/blink/renderer/bindings/core/v8/v8_embedder_graph_builder.cc

@@ -190,7 +190,6 @@ class GC_PLUGIN_IGNORE(
                                void*) final;
   bool VisitEphemeronKeyValuePair(void*,
                                   void*,
-                                  bool,
                                   EphemeronTracingCallback,
                                   EphemeronTracingCallback) final;
 
@@ -732,10 +731,8 @@ void V8EmbedderGraphBuilder::VisitBackingStoreWeakly(
 bool V8EmbedderGraphBuilder::VisitEphemeronKeyValuePair(
     void* key,
     void* value,
-    bool strong_handling,
     EphemeronTracingCallback key_trace_callback,
     EphemeronTracingCallback value_trace_callback) {
-  DCHECK(strong_handling);
   ephemeron_worklist_.push_back(std::unique_ptr<EphemeronItem>{
       new EphemeronItem(key, value, key_trace_callback, value_trace_callback)});
   return true;

third_party/blink/renderer/platform/heap/incremental_marking_test.cc

@@ -59,13 +59,14 @@ class BackingVisitor : public Visitor {
   bool VisitEphemeronKeyValuePair(
       void* key,
       void* value,
-      bool strong_handling,
       EphemeronTracingCallback key_trace_callback,
       EphemeronTracingCallback value_trace_callback) final {
     const bool key_is_dead = key_trace_callback(this, key);
-    if (key_is_dead && !strong_handling)
+    if (key_is_dead)
       return true;
-    return value_trace_callback(this, value);
+    const bool value_is_dead = value_trace_callback(this, value);
+    DCHECK(!value_is_dead);
+    return false;
   }
 
   // Unused overrides.

third_party/blink/renderer/platform/heap/marking_visitor.cc

@@ -110,13 +110,14 @@ void MarkingVisitorCommon::VisitBackingStoreWeakly(
 bool MarkingVisitorCommon::VisitEphemeronKeyValuePair(
     void* key,
     void* value,
-    bool strong_handling,
     EphemeronTracingCallback key_trace_callback,
     EphemeronTracingCallback value_trace_callback) {
   const bool key_is_dead = key_trace_callback(this, key);
-  if (key_is_dead && !strong_handling)
+  if (key_is_dead)
     return true;
-  return value_trace_callback(this, value);
+  const bool value_is_dead = value_trace_callback(this, value);
+  DCHECK(!value_is_dead);
+  return false;
 }
 
 void MarkingVisitorCommon::VisitBackingStoreOnly(void* object,

third_party/blink/renderer/platform/heap/marking_visitor.h

@@ -34,7 +34,6 @@ class PLATFORM_EXPORT MarkingVisitorCommon : public Visitor {
                                void*) final;
   bool VisitEphemeronKeyValuePair(void*,
                                   void*,
-                                  bool,
                                   EphemeronTracingCallback,
                                   EphemeronTracingCallback) final;
 

third_party/blink/renderer/platform/heap/trace_traits.h

@@ -333,7 +333,7 @@ struct TraceKeyValuePairTraits {
   template <>
   static bool Trace<true>(Visitor* visitor, Key& key, Value& value) {
     return visitor->VisitEphemeronKeyValuePair(
-        &key, &value, Strongify,
+        &key, &value,
         TraceCollectionIfEnabled < Strongify ? WTF::kNoWeakHandling
                                              : KeyTraits::kWeakHandlingFlag,
         Key, KeyTraits > ::Trace,

third_party/blink/renderer/platform/heap/visitor.h

@@ -226,7 +226,6 @@ class PLATFORM_EXPORT Visitor {
   virtual bool VisitEphemeronKeyValuePair(
       void* key,
       void* value,
-      bool strong_handling,
       EphemeronTracingCallback key_trace_callback,
       EphemeronTracingCallback value_trace_callback) {
     return true;