[clang-tidy] Fix possible use after move

Minor fixes.

Bug: None
Change-Id: I2270516c27757bceb0e6b3e838ce2004f1d137eb
Reviewed-on: https://chromium-review.googlesource.com/c/1356985Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615971}

content/browser/devtools/devtools_http_handler.cc

@@ -324,7 +324,7 @@ class DevToolsAgentHostClientImpl : public DevToolsAgentHostClient {
 
   ~DevToolsAgentHostClientImpl() override {
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
-    if (agent_host_.get())
+    if (agent_host_)
       agent_host_->DetachClient(this);
   }
 
@@ -356,7 +356,7 @@ class DevToolsAgentHostClientImpl : public DevToolsAgentHostClient {
 
   void OnMessage(const std::string& message) {
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
-    if (agent_host_.get())
+    if (agent_host_)
       agent_host_->DispatchProtocolMessage(this, message);
   }
 
@@ -384,7 +384,7 @@ DevToolsHttpHandler::~DevToolsHttpHandler() {
 }
 
 static std::string PathWithoutParams(const std::string& path) {
-  size_t query_position = path.find("?");
+  size_t query_position = path.find('?');
   if (query_position != std::string::npos)
     return path.substr(0, query_position);
   return path;
@@ -547,13 +547,13 @@ void DevToolsHttpHandler::OnJsonRequest(
 
   // Trim fragment and query
   std::string query;
-  size_t query_pos = path.find("?");
+  size_t query_pos = path.find('?');
   if (query_pos != std::string::npos) {
     query = path.substr(query_pos + 1);
     path = path.substr(0, query_pos);
   }
 
-  size_t fragment_pos = path.find("#");
+  size_t fragment_pos = path.find('#');
   if (fragment_pos != std::string::npos)
     path = path.substr(0, fragment_pos);
 
@@ -652,7 +652,6 @@ void DevToolsHttpHandler::OnJsonRequest(
   }
   SendJson(connection_id, net::HTTP_NOT_FOUND, nullptr,
            "Unknown command: " + command);
-  return;
 }
 
 void DevToolsHttpHandler::DecompressAndSendJsonProtocol(int connection_id) {
@@ -791,7 +790,8 @@ DevToolsHttpHandler::DevToolsHttpHandler(
   base::Thread::Options options;
   options.message_loop_type = base::MessageLoop::TYPE_IO;
   if (thread->StartWithOptions(options)) {
-    thread->task_runner()->PostTask(
+    auto task_runner = thread->task_runner();
+    task_runner->PostTask(
         FROM_HERE,
         base::BindOnce(&StartServerOnHandlerThread, weak_factory_.GetWeakPtr(),
                        std::move(thread), std::move(socket_factory),