[ic] Cache weak cells containing prototypes in respective PrototypeInfo objects.

src/ic/x87/handler-compiler-x87.cc

Index: src/ic/x87/handler-compiler-x87.cc
diff --git a/src/ic/x87/handler-compiler-x87.cc b/src/ic/x87/handler-compiler-x87.cc
index 5eca3dc0cb7bc0d07d9943f0d2dd4e359d5c17c5..02a782a75b0ac4d868db1cd73a975a7353300ac3 100644
--- a/src/ic/x87/handler-compiler-x87.cc
+++ b/src/ic/x87/handler-compiler-x87.cc
@@ -491,8 +491,9 @@ Register PropertyHandlerCompiler::CheckPrototypes(
                  NameDictionary::kNotFound);
 
       if (depth > 1) {
-        // TODO(jkummerow): Cache and re-use weak cell.
-        __ LoadWeakValue(reg, isolate()->factory()->NewWeakCell(current), miss);
+        Handle<WeakCell> weak_cell =
+            Map::GetOrCreatePrototypeWeakCell(current, isolate());
+        __ LoadWeakValue(reg, weak_cell, miss);
       }
       GenerateDictionaryNegativeLookup(masm(), miss, reg, name, scratch1,
                                        scratch2);
@@ -511,7 +512,9 @@ Register PropertyHandlerCompiler::CheckPrototypes(
 
   bool return_holder = return_what == RETURN_HOLDER;
   if (return_holder && depth != 0) {
-    __ LoadWeakValue(reg, isolate()->factory()->NewWeakCell(current), miss);
+    Handle<WeakCell> weak_cell =
+        Map::GetOrCreatePrototypeWeakCell(current, isolate());
+    __ LoadWeakValue(reg, weak_cell, miss);
   }
 
   // Return the register containing the holder.