Allocate filler objects in the factory.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index 869ea3ee1d78110af9969cd378a126a6fbf9da39..3e690cf5ff02093b6224676f0c4b8019564fc8ad 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -755,6 +755,12 @@ class Heap {
   MUST_USE_RESULT MaybeObject* AllocatePartialMap(InstanceType instance_type,
                                                   int instance_size);
 
+  // Allocate a block of memory in the given space (filled with a filler).
+  // Used as a fall-back for generated code when the space is full.
+  MUST_USE_RESULT MaybeObject* AllocateFillerObject(int size,
+                                                    bool double_align,
+                                                    AllocationSpace space);
+
   // Allocates an empty PolymorphicCodeCache.
   MUST_USE_RESULT MaybeObject* AllocatePolymorphicCodeCache();