Fix scoped_refptr construction from NULL

This is a precursor to adding a new scoped_refptr(std::nullptr_t)
constructor. The implicit conversion from NULL to scoped_refptr<T>
causes a compilation error with the new constructor. Replace NULL with
nullptr in any files where this is a problem.

This CL was uploaded by git cl split.

R=garykac@chromium.org

Bug: 1018887
Change-Id: I4b920ec60b5a24237396d7cf14a47c8fcac7d786
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1884954
Auto-Submit: kylechar <kylechar@chromium.org>
Reviewed-by: Gary Kacmarcik <garykac@chromium.org>
Commit-Queue: Gary Kacmarcik <garykac@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710054}

remoting/base/auto_thread.cc

@@ -101,7 +101,7 @@ scoped_refptr<AutoThreadTaskRunner> AutoThread::CreateWithLoopAndComInitTypes(
 #endif
 
 AutoThread::AutoThread(const char* name)
-  : startup_data_(NULL),
+    : startup_data_(nullptr),
 #if defined(OS_WIN)
       com_init_type_(COM_INIT_NONE),
 #endif
@@ -112,7 +112,7 @@ AutoThread::AutoThread(const char* name)
 }
 
 AutoThread::AutoThread(const char* name, AutoThreadTaskRunner* joiner)
-  : startup_data_(NULL),
+    : startup_data_(nullptr),
 #if defined(OS_WIN)
       com_init_type_(COM_INIT_NONE),
 #endif
@@ -146,8 +146,8 @@ scoped_refptr<AutoThreadTaskRunner> AutoThread::StartWithType(
 
   if (!base::PlatformThread::Create(0, this, &thread_)) {
     DLOG(ERROR) << "failed to create thread";
-    startup_data_ = NULL;
-    return NULL;
+    startup_data_ = nullptr;
+    return nullptr;
   }
 
   // Wait for the thread to start and initialize single_thread_task_executor
@@ -159,8 +159,8 @@ scoped_refptr<AutoThreadTaskRunner> AutoThread::StartWithType(
   base::ScopedAllowBaseSyncPrimitivesOutsideBlockingScope allow_wait;
   startup_data.event.Wait();
 
-  // set it to NULL so we don't keep a pointer to some object on the stack.
-  startup_data_ = NULL;
+  // set it to null so we don't keep a pointer to some object on the stack.
+  startup_data_ = nullptr;
 
   DCHECK(startup_data.task_runner.get());
   return startup_data.task_runner;

remoting/base/rsa_key_pair.cc

@@ -34,7 +34,7 @@ scoped_refptr<RsaKeyPair> RsaKeyPair::Generate() {
       crypto::RSAPrivateKey::Create(2048));
   if (!key) {
     LOG(ERROR) << "Cannot generate private key.";
-    return NULL;
+    return nullptr;
   }
   return new RsaKeyPair(std::move(key));
 }
@@ -45,7 +45,7 @@ scoped_refptr<RsaKeyPair> RsaKeyPair::FromString(
   std::string key_str;
   if (!base::Base64Decode(key_base64, &key_str)) {
     LOG(ERROR) << "Failed to decode private key.";
-    return NULL;
+    return nullptr;
   }
 
   std::vector<uint8_t> key_buf(key_str.begin(), key_str.end());
@@ -53,7 +53,7 @@ scoped_refptr<RsaKeyPair> RsaKeyPair::FromString(
       crypto::RSAPrivateKey::CreateFromPrivateKeyInfo(key_buf));
   if (!key) {
     LOG(ERROR) << "Invalid private key.";
-    return NULL;
+    return nullptr;
   }
 
   return new RsaKeyPair(std::move(key));
@@ -61,7 +61,7 @@ scoped_refptr<RsaKeyPair> RsaKeyPair::FromString(
 
 std::string RsaKeyPair::ToString() const {
   // Check that the key initialized.
-  DCHECK(key_.get() != NULL);
+  DCHECK(key_.get() != nullptr);
 
   std::vector<uint8_t> key_buf;
   CHECK(key_->ExportPrivateKey(&key_buf));