[wrapper-tracing] Use name for missed write barriers

This avoids writing a pointer for each traced wrapper on dispatch. It
also brings the wrapper tracing descriptor closer to the regular trace
descriptor.

Bug: chromium:841830
Change-Id: I6be7566a465184b12d9021926b3a61cd66934bc6
Reviewed-on: https://chromium-review.googlesource.com/1067572Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561335}

third_party/blink/renderer/platform/bindings/script_wrappable_visitor_verifier.h

@@ -5,7 +5,9 @@
 #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SCRIPT_WRAPPABLE_VISITOR_VERIFIER_H_
 #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SCRIPT_WRAPPABLE_VISITOR_VERIFIER_H_
 
+#include "base/logging.h"
 #include "third_party/blink/renderer/platform/bindings/script_wrappable_visitor.h"
+#include "third_party/blink/renderer/platform/heap/gc_info.h"
 
 namespace blink {
 
@@ -16,21 +18,22 @@ class ScriptWrappableVisitorVerifier final : public ScriptWrappableVisitor {
  protected:
   void Visit(const TraceWrapperV8Reference<v8::Value>&) final {}
   void Visit(const TraceWrapperDescriptor& descriptor) final {
-    if (!HeapObjectHeader::FromPayload(descriptor.base_object_payload)
-             ->IsWrapperHeaderMarked()) {
-      // If this branch is hit, it means that a white (not discovered by
-      // traceWrappers) object was assigned as a member to a black object
-      // (already processed by traceWrappers). Black object will not be
-      // processed anymore so White object will remain undetected and
-      // therefore its wrapper and all wrappers reachable from it would be
-      // collected.
-
-      // This means there is a write barrier missing somewhere. Check the
-      // backtrace to see which types are causing this and review all the
-      // places where white object is set to a black object.
-      descriptor.missed_write_barrier_callback();
-      NOTREACHED();
-    }
+    HeapObjectHeader* header =
+        HeapObjectHeader::FromPayload(descriptor.base_object_payload);
+    const char* name = GCInfoTable::Get()
+                           .GCInfoFromIndex(header->GcInfoIndex())
+                           ->name_(descriptor.base_object_payload);
+    // If this FATAL is hit, it means that a white (not discovered by
+    // TraceWrappers) object was assigned as a member to a black object (already
+    // processed by TraceWrappers). The black object will not be processed
+    // anymore so white object will remain undetected and therefore its wrapper
+    // and all wrappers reachable from it would be collected.
+    //
+    // This means there is a write barrier missing somewhere. Check the
+    // backtrace to see which types are causing this and review all the places
+    // where white object is set to a black object.
+    LOG_IF(FATAL, !header->IsWrapperHeaderMarked())
+        << "Write barrier missed for " << name;
   }
   void Visit(DOMWrapperMap<ScriptWrappable>*,
              const ScriptWrappable* key) final {}

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

@@ -28,7 +28,6 @@ using TraceCallback = VisitorCallback;
 using TraceWrappersCallback = void (*)(ScriptWrappableVisitor*, void*);
 using WeakCallback = VisitorCallback;
 using EphemeronCallback = VisitorCallback;
-using MissedWriteBarrierCallback = void (*)();
 using NameCallback = const char* (*)(const void* self);
 
 // Callback used for unit testing the marking of conservative pointers

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

@@ -58,7 +58,6 @@ struct TraceWrapperDescriptor {
   STACK_ALLOCATED();
   void* base_object_payload;
   TraceWrappersCallback trace_wrappers_callback;
-  MissedWriteBarrierCallback missed_write_barrier_callback;
 };
 
 // The GarbageCollectedMixin interface and helper macro
@@ -114,7 +113,7 @@ class PLATFORM_EXPORT GarbageCollectedMixin {
     return {BlinkGC::kNotFullyConstructedObject, nullptr, false};
   }
   virtual TraceWrapperDescriptor GetTraceWrapperDescriptor() const {
-    return {BlinkGC::kNotFullyConstructedObject, nullptr, nullptr};
+    return {BlinkGC::kNotFullyConstructedObject, nullptr};
   }
 };
 
@@ -135,8 +134,7 @@ class PLATFORM_EXPORT GarbageCollectedMixin {
                                                                              \
   TraceWrapperDescriptor GetTraceWrapperDescriptor() const override {        \
     return {const_cast<TYPE*>(static_cast<const TYPE*>(this)),               \
-            TraceTrait<TYPE>::TraceWrappers,                                 \
-            ScriptWrappableVisitor::MissedWriteBarrier<TYPE>};               \
+            TraceTrait<TYPE>::TraceWrappers};                                \
   }                                                                          \
                                                                              \
  private:

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

@@ -55,8 +55,7 @@ class AdjustPointerTrait<T, false> {
   }
 
   static TraceWrapperDescriptor GetTraceWrapperDescriptor(void* self) {
-    return {self, TraceTrait<T>::TraceWrappers,
-            ScriptWrappableVisitor::MissedWriteBarrier<T>};
+    return {self, TraceTrait<T>::TraceWrappers};
   }
 
   static HeapObjectHeader* GetHeapObjectHeader(void* self) {