Fix assigning NULL to scoped_refptr

Update code where NULL or 0 is assigned to a scoped_refptr to reset it. Just
call reset() instead. If operator=(std::nullptr_t) is added these assignments
become ambiguous.

This CL was uploaded by git cl split.

R=lambroslambrou@chromium.org

Bug: 1024981
Change-Id: If554e4d375338cb2a814196a4436694cf697f8da
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1918223
Auto-Submit: kylechar <kylechar@chromium.org>
Reviewed-by: Lambros Lambrou <lambroslambrou@chromium.org>
Commit-Queue: Lambros Lambrou <lambroslambrou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715476}

remoting/base/auto_thread_task_runner_unittest.cc

@@ -33,7 +33,7 @@ TEST(AutoThreadTaskRunnerTest, StartAndStop) {
   task_environment.GetMainThreadTaskRunner()->PostTask(
       FROM_HERE, base::BindOnce(&SetFlagTask, &success));
 
-  task_runner = NULL;
+  task_runner.reset();
   run_loop.Run();
   EXPECT_TRUE(success);
 }

remoting/base/auto_thread_unittest.cc

@@ -61,7 +61,7 @@ class AutoThreadTest : public testing::Test {
     // Release |main_task_runner_|, then run |task_environment_| until
     // other references created in tests are gone.  We also post a delayed quit
     // task to |message_loop_| so the test will not hang on failure.
-    main_task_runner_ = NULL;
+    main_task_runner_.reset();
     base::RunLoop run_loop;
     quit_closure_ = run_loop.QuitClosure();
     task_environment_.GetMainThreadTaskRunner()->PostDelayedTask(
@@ -95,7 +95,7 @@ TEST_F(AutoThreadTest, StartAndStop) {
       AutoThread::Create(kThreadName, main_task_runner_);
   EXPECT_TRUE(task_runner);
 
-  task_runner = NULL;
+  task_runner.reset();
   RunMessageLoop();
 }
 
@@ -109,7 +109,7 @@ TEST_F(AutoThreadTest, ProcessTask) {
   bool success = false;
   task_runner->PostTask(FROM_HERE, base::BindOnce(&SetFlagTask, &success));
 
-  task_runner = NULL;
+  task_runner.reset();
   RunMessageLoop();
 
   EXPECT_TRUE(success);
@@ -129,8 +129,8 @@ TEST_F(AutoThreadTest, ThreadDependency) {
   task_runner1->PostTask(
       FROM_HERE, base::BindOnce(&PostSetFlagTask, task_runner2, &success));
 
-  task_runner1 = NULL;
-  task_runner2 = NULL;
+  task_runner1.reset();
+  task_runner2.reset();
   RunMessageLoop();
 
   EXPECT_TRUE(success);
@@ -150,7 +150,7 @@ TEST_F(AutoThreadTest, ThreadWithComMta) {
   task_runner->PostTask(
       FROM_HERE, base::BindOnce(&CheckComAptTypeTask, &apt_type, &hresult));
 
-  task_runner = NULL;
+  task_runner.reset();
   RunMessageLoop();
 
   EXPECT_EQ(S_OK, hresult);
@@ -170,7 +170,7 @@ TEST_F(AutoThreadTest, ThreadWithComSta) {
   task_runner->PostTask(
       FROM_HERE, base::BindOnce(&CheckComAptTypeTask, &apt_type, &hresult));
 
-  task_runner = NULL;
+  task_runner.reset();
   RunMessageLoop();
 
   EXPECT_EQ(S_OK, hresult);

remoting/base/socket_reader.cc

@@ -55,7 +55,7 @@ void SocketReader::OnRead(int result) {
 void SocketReader::HandleReadResult(int result) {
   if (result != net::ERR_IO_PENDING) {
     if (result < 0)
-      read_buffer_ = NULL;
+      read_buffer_.reset();
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::BindOnce(&SocketReader::CallCallback, weak_factory_.GetWeakPtr(),

remoting/protocol/channel_socket_adapter.cc

@@ -112,14 +112,14 @@ void TransportChannelSocketAdapter::Close(int error_code) {
   if (!read_callback_.is_null()) {
     net::CompletionRepeatingCallback callback = read_callback_;
     read_callback_.Reset();
-    read_buffer_ = NULL;
+    read_buffer_.reset();
     callback.Run(error_code);
   }
 
   if (!write_callback_.is_null()) {
     net::CompletionRepeatingCallback callback = write_callback_;
     write_callback_.Reset();
-    write_buffer_ = NULL;
+    write_buffer_.reset();
     callback.Run(error_code);
   }
 }
@@ -146,7 +146,7 @@ void TransportChannelSocketAdapter::OnNewPacket(
 
     net::CompletionRepeatingCallback callback = read_callback_;
     read_callback_.Reset();
-    read_buffer_ = NULL;
+    read_buffer_.reset();
     callback.Run(data_size);
   } else {
     LOG(WARNING)
@@ -169,7 +169,7 @@ void TransportChannelSocketAdapter::OnWritableState(
     if (result != net::ERR_IO_PENDING) {
       net::CompletionRepeatingCallback callback = write_callback_;
       write_callback_.Reset();
-      write_buffer_ = NULL;
+      write_buffer_.reset();
       callback.Run(result);
     }
   }

remoting/protocol/pseudotcp_adapter.cc

@@ -245,7 +245,7 @@ void PseudoTcpAdapter::Core::OnTcpReadable(PseudoTcp* tcp) {
 
   AdjustClock();
 
-  read_buffer_ = NULL;
+  read_buffer_.reset();
   std::move(read_callback_).Run(result);
 }
 
@@ -276,7 +276,7 @@ void PseudoTcpAdapter::Core::OnTcpWriteable(PseudoTcp* tcp) {
     return;
   }
 
-  write_buffer_ = NULL;
+  write_buffer_.reset();
   std::move(write_callback_).Run(result);
 }
 
@@ -319,9 +319,9 @@ void PseudoTcpAdapter::Core::SetWriteWaitsForSend(bool write_waits_for_send) {
 void PseudoTcpAdapter::Core::DeleteSocket() {
   // Don't dispatch outstanding callbacks when the socket is deleted.
   read_callback_.Reset();
-  read_buffer_ = NULL;
+  read_buffer_.reset();
   write_callback_.Reset();
-  write_buffer_ = NULL;
+  write_buffer_.reset();
   connect_callback_.Reset();
 
   socket_.reset();
@@ -436,7 +436,7 @@ void PseudoTcpAdapter::Core::CheckWriteComplete() {
     if (pseudo_tcp_.GetBytesBufferedNotSent() == 0) {
       waiting_write_position_ = false;
 
-      write_buffer_ = NULL;
+      write_buffer_.reset();
       std::move(write_callback_).Run(last_write_result_);
     }
   }

remoting/protocol/pseudotcp_adapter_unittest.cc

@@ -94,7 +94,7 @@ class FakeSocket : public P2PDatagramSocket {
       memcpy(read_buffer_->data(), &data[0], data.size());
       net::CompletionRepeatingCallback cb = read_callback_;
       read_callback_.Reset();
-      read_buffer_ = NULL;
+      read_buffer_.reset();
       cb.Run(size);
     } else {
       incoming_packets_.push_back(data);