Inline Map::has_code_cache() into its one caller.

R=verwaest@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2957313002
Cr-Commit-Position: refs/heads/master@{#46310}

src/heap/object-stats.cc

@@ -462,8 +462,8 @@ void ObjectStatsCollector::RecordMapDetails(Map* map_obj) {
     }
   }
 
-  if (map_obj->has_code_cache()) {
-    FixedArray* code_cache = map_obj->code_cache();
+  FixedArray* code_cache = map_obj->code_cache();
+  if (code_cache->length() > 0) {
     if (code_cache->IsCodeCacheHashTable()) {
       RecordHashTableHelper(map_obj, CodeCacheHashTable::cast(code_cache),
                             MAP_CODE_CACHE_SUB_TYPE);

src/objects-inl.h

@@ -3614,13 +3614,6 @@ bool Map::is_stable() {
 }
 
 
-bool Map::has_code_cache() {
-  // Code caches are always fixed arrays. The empty fixed array is used as a
-  // sentinel for an absent code cache.
-  return code_cache()->length() != 0;
-}
-
-
 bool Map::CanBeDeprecated() {
   int descriptor = LastAdded();
   for (int i = 0; i <= descriptor; i++) {

src/objects/map.h

@@ -320,9 +320,6 @@ class Map : public HeapObject {
   inline void set_is_access_check_needed(bool access_check_needed);
   inline bool is_access_check_needed();
 
-  // Returns true if map has a non-empty stub code cache.
-  inline bool has_code_cache();
-
   // [prototype]: implicit prototype object.
   DECL_ACCESSORS(prototype, Object)
   // TODO(jkummerow): make set_prototype private.