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=raymes@chromium.org

Bug: 1024981
Change-Id: Ia3973b95ed896197678e47de7697f68c3ab2e784
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1918156
Auto-Submit: kylechar <kylechar@chromium.org>
Reviewed-by: Raymes Khoury <raymes@chromium.org>
Commit-Queue: kylechar <kylechar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715710}

ppapi/proxy/file_io_resource.cc

@@ -402,7 +402,7 @@ void FileIOResource::Close() {
   }
 
   if (file_holder_.get())
-    file_holder_ = NULL;
+    file_holder_.reset();
 
   Post(BROWSER, PpapiHostMsg_FileIO_Close(
       FileGrowth(max_written_offset_, append_mode_write_amount_)));
@@ -669,7 +669,7 @@ void FileIOResource::OnPluginMsgOpenFileComplete(
          FileIOStateManager::OPERATION_EXCLUSIVE);
 
   // Release the FileRef resource.
-  file_ref_ = NULL;
+  file_ref_.reset();
   int32_t result = params.result();
   if (result == PP_OK) {
     state_manager_.SetOpenSucceed();

ppapi/proxy/media_stream_audio_track_resource.cc

@@ -142,7 +142,7 @@ void MediaStreamAudioTrackResource::Close() {
   if (TrackedCallback::IsPending(get_buffer_callback_)) {
     *get_buffer_output_ = 0;
     get_buffer_callback_->PostAbort();
-    get_buffer_callback_ = NULL;
+    get_buffer_callback_.reset();
     get_buffer_output_ = 0;
   }
 
@@ -183,7 +183,7 @@ void MediaStreamAudioTrackResource::ReleaseBuffers() {
     // Just invalidate and release VideoBufferResorce, but keep PP_Resource.
     // So plugin can still use |RecycleBuffer()|.
     it->second->Invalidate();
-    it->second = NULL;
+    it->second.reset();
   }
 }
 

ppapi/proxy/media_stream_video_track_resource.cc

@@ -151,7 +151,7 @@ void MediaStreamVideoTrackResource::Close() {
   if (TrackedCallback::IsPending(get_frame_callback_)) {
     *get_frame_output_ = 0;
     get_frame_callback_->PostAbort();
-    get_frame_callback_ = NULL;
+    get_frame_callback_.reset();
     get_frame_output_ = 0;
   }
 
@@ -203,7 +203,7 @@ void MediaStreamVideoTrackResource::ReleaseFrames() {
     // Just invalidate and release VideoFrameResorce, but keep PP_Resource.
     // So plugin can still use |RecycleFrame()|.
     it->second->Invalidate();
-    it->second = NULL;
+    it->second.reset();
   }
 }
 

ppapi/proxy/plugin_globals.cc

@@ -97,7 +97,7 @@ PluginGlobals::~PluginGlobals() {
     // we clear plugin_globals_, because the Resource destructor tries to access
     // this PluginGlobals.
     DCHECK(!loop_for_main_thread_.get() || loop_for_main_thread_->HasOneRef());
-    loop_for_main_thread_ = NULL;
+    loop_for_main_thread_.reset();
   }
   plugin_globals_ = NULL;
 }

ppapi/proxy/plugin_var_tracker_unittest.cc

@@ -209,7 +209,7 @@ TEST_F(PluginVarTrackerTest, PluginObjectInstanceDeleted) {
 
   // Release the plugin ref to the var. WebKit hasn't called destroy so
   // we won't get a destroy call.
-  object = NULL;
+  object.reset();
   var_tracker().ReleaseVar(plugin_var);
   EXPECT_EQ(0, deallocate_called);
 
@@ -243,7 +243,7 @@ TEST_F(PluginVarTrackerTest, PluginObjectLeaked) {
 
   // Release the plugin ref to the var. Since the instance is gone this should
   // call deallocate.
-  object = NULL;
+  object.reset();
   var_tracker().ReleaseVar(plugin_var);
   EXPECT_EQ(1, deallocate_called);
 }

ppapi/proxy/ppapi_proxy_test.cc

@@ -371,12 +371,12 @@ void PluginProxyMultiThreadTest::RunTest() {
 
     // The destruction requires a valid PpapiGlobals instance, so we should
     // explicitly release it.
-    secondary_thread_message_loop_ = NULL;
+    secondary_thread_message_loop_.reset();
   }
 
   secondary_thread_.reset(NULL);
   nested_main_thread_message_loop_.reset(NULL);
-  main_thread_task_runner_ = NULL;
+  main_thread_task_runner_.reset();
 }
 
 void PluginProxyMultiThreadTest::CheckOnThread(ThreadType thread_type) {

ppapi/proxy/ppb_message_loop_proxy.cc

@@ -122,7 +122,7 @@ int32_t MessageLoopResource::Run() {
   run_loop_ = previous_run_loop;
 
   if (should_destroy_ && nested_invocations_ == 0) {
-    task_runner_ = NULL;
+    task_runner_.reset();
     single_thread_task_executor_.reset();
     destroyed_ = true;
   }
@@ -171,7 +171,7 @@ MessageLoopResource* MessageLoopResource::GetCurrent() {
 void MessageLoopResource::DetachFromThread() {
   // Note that the task executor must be destroyed on the thread it was created
   // on.
-  task_runner_ = NULL;
+  task_runner_.reset();
   single_thread_task_executor_.reset();
 
   // Cancel out the AddRef in AttachToCurrentThread().

ppapi/proxy/tcp_socket_resource_base.cc

@@ -308,7 +308,7 @@ void TCPSocketResourceBase::CloseImpl() {
   PostAbortIfNecessary(&accept_callback_);
   read_buffer_ = NULL;
   bytes_to_read_ = -1;
-  server_certificate_ = NULL;
+  server_certificate_.reset();
   accepted_tcp_socket_ = NULL;
 }
 

ppapi/proxy/uma_private_resource.cc

@@ -102,7 +102,7 @@ void UMAPrivateResource::OnPluginMsgIsCrashReportingEnabled(
     const ResourceMessageReplyParams& params) {
   if (TrackedCallback::IsPending(pending_callback_))
     pending_callback_->Run(params.result());
-  pending_callback_ = NULL;
+  pending_callback_.reset();
 }
 
 }  // namespace proxy

ppapi/proxy/video_decoder_resource.cc

@@ -335,10 +335,10 @@ int32_t VideoDecoderResource::Reset(scoped_refptr<TrackedCallback> callback) {
   // to avoid reentering the plugin.
   if (TrackedCallback::IsPending(decode_callback_))
     decode_callback_->PostAbort();
-  decode_callback_ = NULL;
+  decode_callback_.reset();
   if (TrackedCallback::IsPending(get_picture_callback_))
     get_picture_callback_->PostAbort();
-  get_picture_callback_ = NULL;
+  get_picture_callback_.reset();
   Call<PpapiPluginMsg_VideoDecoder_ResetReply>(
       RENDERER,
       PpapiHostMsg_VideoDecoder_Reset(),

ppapi/shared_impl/resource_tracker_unittest.cc

@@ -72,7 +72,7 @@ TEST_F(ResourceTrackerTest, LastPluginRef) {
   EXPECT_EQ(1, mock_resource_alive_count);
 
   resource_tracker().DidDeleteInstance(instance);
-  resource = NULL;
+  resource.reset();
   EXPECT_FALSE(resource_tracker().GetResource(pp_resource));
 }
 
@@ -117,7 +117,7 @@ TEST_F(ResourceTrackerTest, InstanceDeletedWithBothRefed) {
   EXPECT_EQ(1, instance_was_deleted_count);
   EXPECT_EQ(0, resource->pp_instance());
 
-  resource = NULL;
+  resource.reset();
   EXPECT_EQ(0, mock_resource_alive_count);
 }
 

ppapi/shared_impl/tracked_callback.cc

@@ -230,13 +230,13 @@ void TrackedCallback::MarkAsCompletedWithLock() {
   // We may not have a valid resource, in which case we're not in the tracker.
   if (resource_id_)
     tracker_->Remove(thiz);
-  tracker_ = NULL;
+  tracker_.reset();
 
   // Relax the cross-thread access restriction to non-thread-safe RefCount.
   // |lock_| protects the access to Resource instances.
   base::ScopedAllowCrossThreadRefCountAccess
       allow_cross_thread_ref_count_access;
-  target_loop_ = NULL;
+  target_loop_.reset();
 }
 
 void TrackedCallback::PostRunWithLock(int32_t result) {

ppapi/shared_impl/var_tracker_unittest.cc

@@ -69,7 +69,7 @@ TEST_F(VarTrackerTest, LastResourceRef) {
   EXPECT_FALSE(var->HasValidVarID());
   EXPECT_EQ(1, mock_var_alive_count);
 
-  var = NULL;
+  var.reset();
   EXPECT_EQ(0, mock_var_alive_count);
 }
 
@@ -94,10 +94,10 @@ TEST_F(VarTrackerTest, GetPluginRefAgain) {
   EXPECT_FALSE(var->HasValidVarID());
   EXPECT_EQ(1, mock_var_alive_count);
 
-  var = NULL;
+  var.reset();
   EXPECT_FALSE(var_tracker().GetVar(pp_var));
   EXPECT_EQ(1, mock_var_alive_count);
-  another_var = NULL;
+  another_var.reset();
   EXPECT_FALSE(var_tracker().GetVar(pp_var));
   EXPECT_EQ(0, mock_var_alive_count);
 }
@@ -110,7 +110,7 @@ TEST_F(VarTrackerTest, PluginRefWithoutVarRef) {
   scoped_refptr<MockStringVar> var(new MockStringVar(std::string("zzz")));
   PP_Var pp_var = var->GetPPVar();
   EXPECT_EQ(1, mock_var_alive_count);
-  var = NULL;
+  var.reset();
   EXPECT_EQ(1, mock_var_alive_count);
 
   // The var is owned only by VarTracker. PP_Var must be still valid.
@@ -139,10 +139,10 @@ TEST_F(VarTrackerTest, ObjectRef) {
   EXPECT_EQ(1, mock_var_alive_count);
 
   // Releasing all references, then only VarTracker own the instance.
-  var = NULL;
+  var.reset();
   EXPECT_TRUE(var_tracker().GetVar(pp_var));
   EXPECT_EQ(1, mock_var_alive_count);
-  another_var = NULL;
+  another_var.reset();
   EXPECT_TRUE(var_tracker().GetVar(pp_var));
   EXPECT_EQ(1, mock_var_alive_count);