Avoid duplicate functions/code in core/inspector.

third_party/WebKit/Source/core/inspector/IdentifiersFactory.cpp

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 40 matching lines @@
 String IdentifiersFactory::RequestId(unsigned long identifier) {
   return identifier ? AddProcessIdPrefixTo(identifier) : String();
 }
 
 // static
 String IdentifiersFactory::FrameId(LocalFrame* frame) {
   return AddProcessIdPrefixTo(WeakIdentifierMap<LocalFrame>::Identifier(frame));
 }
 
 // static
+String IdentifiersFactory::FrameIdSafe(LocalFrame* frame) {
+  return frame ? FrameId(frame) : "";

[pfeldman, 2017/07/21 18:10:59]

Bake it into FrameId(), return String() if nullptr is passed.

[Daniel Bratell, 2017/07/23 20:14:12]

Done.

+}
+
+// static
 LocalFrame* IdentifiersFactory::FrameById(InspectedFrames* inspected_frames,
                                           const String& frame_id) {
   bool ok;
   int id = RemoveProcessIdPrefixFrom(frame_id, &ok);
   if (!ok)
     return nullptr;
   LocalFrame* frame = WeakIdentifierMap<LocalFrame>::Lookup(id);
   return frame && inspected_frames->Contains(frame) ? frame : nullptr;
 }
 
@@ skipping 34 matching lines @@
   size_t dot_index = id.find('.');
 
   if (dot_index == kNotFound) {
     *ok = false;
     return 0;
   }
   return id.Substring(dot_index + 1).ToInt(ok);
 }
 
 }  // namespace blink