[runtime] Port simple String.prototype.indexOf cases to TF Builtin

test/cctest/cctest.h

 // Copyright 2008 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 565 matching lines @@
   ~InitializedHandleScope();
 
   // Prefixing the below with main_ reduces a lot of naming clashes.
   i::Isolate* main_isolate() { return main_isolate_; }
 
  private:
   i::Isolate* main_isolate_;
   std::unique_ptr<InitializedHandleScopeImpl> initialized_handle_scope_impl_;
 };
 
-
 class HandleAndZoneScope : public InitializedHandleScope {
  public:
   HandleAndZoneScope();
   ~HandleAndZoneScope();
 
   // Prefixing the below with main_ reduces a lot of naming clashes.
   i::Zone* main_zone() { return main_zone_.get(); }
 
  private:
   v8::internal::AccountingAllocator allocator_;
   std::unique_ptr<i::Zone> main_zone_;
 };
 
+class StaticOneByteResource : public v8::String::ExternalOneByteStringResource {
+ public:
+  explicit StaticOneByteResource(const char* data) : data_(data) {}
+
+  ~StaticOneByteResource() {}
+
+  const char* data() const { return data_; }
+
+  size_t length() const { return strlen(data_); }
+
+ private:
+  const char* data_;
+};
+
 #endif  // ifndef CCTEST_H_