[DevTools] Added more null check into DispatcherBase template

third_party/WebKit/Source/platform/inspector_protocol/lib/DispatcherBase_cpp.template

 // 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 "DispatcherBase.h"
 //#include "Parser.h"
 
 {% for namespace in config.protocol.namespace %}
 namespace {{namespace}} {
 {% endfor %}
@@ skipping 72 matching lines @@
     sendResponse(callId, invocationError, nullptr, std::move(result));
 }
 
 void DispatcherBase::sendResponse(int callId, const ErrorString& invocationError)
 {
     sendResponse(callId, invocationError, nullptr, DictionaryValue::create());
 }
 
 static void reportProtocolErrorTo(FrontendChannel* frontendChannel, int callId, DispatcherBase::CommonErrorCode code, const String& errorMessage, ErrorSupport* errors)
 {
+    if (!frontendChannel)
+        return;
     std::unique_ptr<protocol::DictionaryValue> error = DictionaryValue::create();
     error->setInteger("code", code);
     error->setString("message", errorMessage);
     DCHECK(error);
     if (errors && errors->hasErrors())
         error->setString("data", errors->errors());
     std::unique_ptr<protocol::DictionaryValue> message = DictionaryValue::create();
     message->setObject("error", std::move(error));
     message->setInteger("id", callId);
     frontendChannel->sendProtocolResponse(callId, message->toJSONString());
 }
 
 void DispatcherBase::reportProtocolError(int callId, CommonErrorCode code, const String& errorMessage, ErrorSupport* errors)
 {
-    if (m_frontendChannel)
-        reportProtocolErrorTo(m_frontendChannel, callId, code, errorMessage, errors);
+    reportProtocolErrorTo(m_frontendChannel, callId, code, errorMessage, errors);
 }
 
 void DispatcherBase::clearFrontend()
 {
     m_frontendChannel = nullptr;
     for (auto& weak : m_weakPtrs)
         weak->dispose();
     m_weakPtrs.clear();
 }
 
@@ skipping 15 matching lines @@
 void UberDispatcher::dispatch(std::unique_ptr<Value> parsedMessage)
 {
     if (!parsedMessage)
         return;
     std::unique_ptr<protocol::DictionaryValue> messageObject = DictionaryValue::cast(std::move(parsedMessage));
     if (!messageObject)
         return;
 
     int callId = 0;
     protocol::Value* callIdValue = messageObject->get("id");
-    bool success = callIdValue->asInteger(&callId);
+    bool success = callIdValue && callIdValue->asInteger(&callId);
     if (!success)
         return;
 
     protocol::Value* methodValue = messageObject->get("method");
     String method;
     success = methodValue && methodValue->asString(&method);
     if (!success)
         return;
 
     size_t dotIndex = method.find(".");
     if (dotIndex == StringUtil::kNotFound) {
         reportProtocolErrorTo(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
         return;
     }
     String domain = StringUtil::substring(method, 0, dotIndex);
     auto it = m_dispatchers.find(domain);
     if (it == m_dispatchers.end()) {
         reportProtocolErrorTo(m_frontendChannel, callId, DispatcherBase::MethodNotFound, "'" + method + "' wasn't found", nullptr);
         return;
     }
     it->second->dispatch(callId, method, std::move(messageObject));
 }
 
 UberDispatcher::~UberDispatcher() = default;
 
 {% for namespace in config.protocol.namespace %}
 } // namespace {{namespace}}
 {% endfor %}