[cleanup] Make DebugObjectCache an std::vector.

There's no point in using our own implemention of List for this.

Bug:v8:6333

Change-Id: Ic239c9348bb17d61e41130a18e1c9f16cab9d8ee
Reviewed-on: https://chromium-review.googlesource.com/489503Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Franziska Hinkelmann <franzih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45192}

src/isolate.h

@@ -395,7 +395,7 @@ class ThreadLocalTop BASE_EMBEDDED {
   V(int, suffix_table, (kBMMaxShift + 1))                                      \
   ISOLATE_INIT_DEBUG_ARRAY_LIST(V)
 
-typedef List<HeapObject*> DebugObjectCache;
+typedef std::vector<HeapObject*> DebugObjectCache;
 
 #define ISOLATE_INIT_LIST(V)                                                  \
   /* Assembler state. */                                                      \

src/string-stream.cc

@@ -190,15 +190,15 @@ void StringStream::PrintObject(Object* o) {
     HeapObject* ho = HeapObject::cast(o);
     DebugObjectCache* debug_object_cache = ho->GetIsolate()->
         string_stream_debug_object_cache();
-    for (int i = 0; i < debug_object_cache->length(); i++) {
+    for (size_t i = 0; i < debug_object_cache->size(); i++) {
       if ((*debug_object_cache)[i] == o) {
-        Add("#%d#", i);
+        Add("#%d#", static_cast<int>(i));
         return;
       }
     }
-    if (debug_object_cache->length() < kMentionedObjectCacheMaxSize) {
-      Add("#%d#", debug_object_cache->length());
-      debug_object_cache->Add(HeapObject::cast(o));
+    if (debug_object_cache->size() < kMentionedObjectCacheMaxSize) {
+      Add("#%d#", static_cast<int>(debug_object_cache->size()));
+      debug_object_cache->push_back(HeapObject::cast(o));
     } else {
       Add("@%p", o);
     }
@@ -244,16 +244,16 @@ Handle<String> StringStream::ToString(Isolate* isolate) {
 void StringStream::ClearMentionedObjectCache(Isolate* isolate) {
   isolate->set_string_stream_current_security_token(NULL);
   if (isolate->string_stream_debug_object_cache() == NULL) {
-    isolate->set_string_stream_debug_object_cache(new DebugObjectCache(0));
+    isolate->set_string_stream_debug_object_cache(new DebugObjectCache());
   }
-  isolate->string_stream_debug_object_cache()->Clear();
+  isolate->string_stream_debug_object_cache()->clear();
 }
 
 
 #ifdef DEBUG
 bool StringStream::IsMentionedObjectCacheClear(Isolate* isolate) {
   return object_print_mode_ == kPrintObjectConcise ||
-         isolate->string_stream_debug_object_cache()->length() == 0;
+         isolate->string_stream_debug_object_cache()->size() == 0;
 }
 #endif
 
@@ -377,9 +377,9 @@ void StringStream::PrintMentionedObjectCache(Isolate* isolate) {
   DebugObjectCache* debug_object_cache =
       isolate->string_stream_debug_object_cache();
   Add("==== Key         ============================================\n\n");
-  for (int i = 0; i < debug_object_cache->length(); i++) {
+  for (size_t i = 0; i < debug_object_cache->size(); i++) {
     HeapObject* printee = (*debug_object_cache)[i];
-    Add(" #%d# %p: ", i, printee);
+    Add(" #%d# %p: ", static_cast<int>(i), printee);
     printee->ShortPrint(this);
     Add("\n");
     if (printee->IsJSObject()) {