[DevTools] Reduce API surface of String16.

third_party/WebKit/Source/platform/inspector_protocol/DispatcherBase.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/inspector_protocol/DispatcherBase.h"
 
 #include "platform/inspector_protocol/FrontendChannel.h"
 #include "platform/inspector_protocol/Parser.h"
 
 namespace blink {
@@ skipping 136 matching lines @@
     if (!success)
         return;
 
     protocol::Value* methodValue = messageObject->get("method");
     String16 method;
     success = methodValue && methodValue->asString(&method);
     if (!success)
         return;
 
     size_t dotIndex = method.find(".");
-    if (dotIndex == kNotFound) {
+    if (dotIndex == String16::kNotFound) {
         reportProtocolError(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
         return;
     }
     String16 domain = method.substring(0, dotIndex);
     auto it = m_dispatchers.find(domain);
     if (it == m_dispatchers.end()) {
         reportProtocolError(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
         return;
     }
     it->second->dispatch(callId, method, std::move(messageObject));
 }
 
 UberDispatcher::~UberDispatcher() = default;
 
 } // namespace protocol
 } // namespace blink