[v4.x] deps: revert/re-apply 09db540 from upstream v8

deps/v8/include/v8-version.h

@@ -11,7 +11,7 @@
 #define V8_MAJOR_VERSION 4
 #define V8_MINOR_VERSION 5
 #define V8_BUILD_NUMBER 103
-#define V8_PATCH_LEVEL 48
+#define V8_PATCH_LEVEL 49
 
 // Use 1 for candidates and 0 otherwise.
 // (Boolean macro values are not supported by all preprocessors.)

deps/v8/src/heap/mark-compact.cc

@@ -2614,13 +2614,6 @@ void MarkCompactCollector::ClearWeakCollections() {
           table->RemoveEntry(i);
         }
       }
-      // Rehash if more than 25% of the entries are deleted entries.
-      // TODO(jochen): Consider to shrink the fixed array in place.
-      if ((table->NumberOfDeletedElements() << kJSWeakCollectionLoadFactorExp) >
-          table->NumberOfElements()) {
-        HandleScope scope(heap()->isolate());
-        table->Rehash(heap()->isolate()->factory()->undefined_value());
-      }
     }
     weak_collection_obj = weak_collection->next();
     weak_collection->set_next(heap()->undefined_value());

deps/v8/src/heap/mark-compact.h

@@ -612,10 +612,6 @@ class MarkCompactCollector {
   static const uint32_t kSingleFreeEncoding = 0;
   static const uint32_t kMultiFreeEncoding = 1;
 
-  // If the number of deleted slots in a JSWeakCollection exceeds the number
-  // of entries / 2^(factor), we rehash the table.
-  static const int kJSWeakCollectionLoadFactorExp = 1;
-
   static inline bool IsMarked(Object* obj);
   static bool IsUnmarkedHeapObjectWithHeap(Heap* heap, Object** p);
 

deps/v8/src/objects.cc

@@ -14677,7 +14677,6 @@ Handle<CompilationCacheTable> CompilationCacheTable::PutRegExp(
 void CompilationCacheTable::Age() {
   DisallowHeapAllocation no_allocation;
   Object* the_hole_value = GetHeap()->the_hole_value();
-  uint32_t capacity = Capacity();
   for (int entry = 0, size = Capacity(); entry < size; entry++) {
     int entry_index = EntryToIndex(entry);
     int value_index = entry_index + 1;
@@ -14701,16 +14700,6 @@ void CompilationCacheTable::Age() {
       }
     }
   }
-  // Wipe deleted entries.
-  Heap* heap = GetHeap();
-  Object* the_hole = heap->the_hole_value();
-  Object* undefined = heap->undefined_value();
-  for (uint32_t current = 0; current < capacity; current++) {
-    if (get(EntryToIndex(current)) == the_hole) {
-      set(EntryToIndex(current), undefined);
-    }
-  }
-  SetNumberOfDeletedElements(0);
 }
 
 
@@ -15219,7 +15208,7 @@ Handle<ObjectHashTable> ObjectHashTable::Put(Handle<ObjectHashTable> table,
     return table;
   }
 
-  // Rehash if more than 25% of the entries are deleted entries.
+  // Rehash if more than 33% of the entries are deleted entries.
   // TODO(jochen): Consider to shrink the fixed array in place.
   if ((table->NumberOfDeletedElements() << 1) > table->NumberOfElements()) {
     table->Rehash(isolate->factory()->undefined_value());

deps/v8/test/cctest/test-weakmaps.cc

@@ -123,7 +123,7 @@ TEST(Weakness) {
   heap->CollectAllGarbage(false);
   CHECK_EQ(1, NumberOfWeakCalls);
   CHECK_EQ(0, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
-  CHECK_EQ(0,
+  CHECK_EQ(2,
            ObjectHashTable::cast(weakmap->table())->NumberOfDeletedElements());
 }
 

deps/v8/test/cctest/test-weaksets.cc

@@ -122,8 +122,8 @@ TEST(WeakSet_Weakness) {
   heap->CollectAllGarbage(false);
   CHECK_EQ(1, NumberOfWeakCalls);
   CHECK_EQ(0, ObjectHashTable::cast(weakset->table())->NumberOfElements());
-  CHECK_EQ(0,
-           ObjectHashTable::cast(weakset->table())->NumberOfDeletedElements());
+  CHECK_EQ(
+      1, ObjectHashTable::cast(weakset->table())->NumberOfDeletedElements());
 }