Inserted a missing string encoding check in lastIndexOf.

test/cctest/test-api.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 13675 matching lines @@
   // See Chromium issue 47824.
   v8::HandleScope scope;
 
   LocalContext context;
   const char* init_code =
       "var str1 = 'abelspendabel';"
       "var str2 = str1 + str1 + str1;"
       "str2;";
   Local<Value> result = CompileRun(init_code);
 
+  Local<Value> indexof = CompileRun("str2.indexOf('els')");
+  Local<Value> lastindexof = CompileRun("str2.lastIndexOf('dab')");
+
   CHECK(result->IsString());
   i::Handle<i::String> string = v8::Utils::OpenHandle(String::Cast(*result));
   int length = string->length();
   CHECK(string->IsAsciiRepresentation());
 
   FlattenString(string);
   i::Handle<i::String> flat_string = FlattenGetString(string);
 
   CHECK(string->IsAsciiRepresentation());
   CHECK(flat_string->IsAsciiRepresentation());
@@ skipping 45 matching lines @@
 
   reresult = CompileRun("/be./g.exec(str2);");
   CHECK(!reresult->IsNull());
 
   ExpectString("str2.substring(2, 10);", "elspenda");
 
   ExpectString("str2.substring(2, 20);", "elspendabelabelspe");
 
   ExpectString("str2.charAt(2);", "e");
 
+  ExpectObject("str2.indexOf('els');", indexof);
+
+  ExpectObject("str2.lastIndexOf('dab');", lastindexof);
+
   reresult = CompileRun("str2.charCodeAt(2);");
   CHECK_EQ(static_cast<int32_t>('e'), reresult->Int32Value());
 }
 
 
 // Failed access check callback that performs a GC on each invocation.
 void FailedAccessCheckCallbackGC(Local<v8::Object> target,
                                  v8::AccessType type,
                                  Local<v8::Value> data) {
   HEAP->CollectAllGarbage(true);
@@ skipping 1118 matching lines @@
   }
 
   i::Isolate::Current()->heap()->CollectAllGarbage(true);
   { i::Object* raw_map_cache = i::Isolate::Current()->context()->map_cache();
     if (raw_map_cache != i::Isolate::Current()->heap()->undefined_value()) {
       i::MapCache* map_cache = i::MapCache::cast(raw_map_cache);
       CHECK_GT(elements, map_cache->NumberOfElements());
     }
   }
 }