Cleanup MessageLoop::current() usage /content/child

Changes in patch set 1 were scripted as part of the effort to restrict exposure of the
raw MessageLoop*.

I've manually cleaned it up in the latest patch set to remove usage of MessageLoop*
another level.

This CL was uploaded by git cl split (initially).

R=haraken@chromium.org
TBR=piman@chromium.org (naming side-effect in ppapi_plugin/)

Bug: 825327
Change-Id: Id2c1dcb68c7a8fccafa5e0eee86fb5db82939a2f
Reviewed-on: https://chromium-review.googlesource.com/1024654
Commit-Queue: Gabriel Charette <gab@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553539}

content/child/child_process.cc

@@ -101,13 +101,13 @@ void ChildProcess::set_main_thread(ChildThreadImpl* thread) {
 
 void ChildProcess::AddRefProcess() {
   DCHECK(!main_thread_.get() ||  // null in unittests.
-         main_thread_->message_loop()->task_runner()->BelongsToCurrentThread());
+         main_thread_->main_thread_runner()->BelongsToCurrentThread());
   ref_count_++;
 }
 
 void ChildProcess::ReleaseProcess() {
   DCHECK(!main_thread_.get() ||  // null in unittests.
-         main_thread_->message_loop()->task_runner()->BelongsToCurrentThread());
+         main_thread_->main_thread_runner()->BelongsToCurrentThread());
   DCHECK(ref_count_);
   if (--ref_count_)
     return;

content/child/child_thread_impl.cc

@@ -17,7 +17,7 @@
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
-#include "base/message_loop/message_loop.h"
+#include "base/message_loop/message_loop_current.h"
 #include "base/message_loop/timer_slack.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
@@ -208,7 +208,7 @@ void QuitClosure::BindToMainThread() {
   scoped_refptr<base::SingleThreadTaskRunner> task_runner(
       base::ThreadTaskRunnerHandle::Get());
   base::Closure quit_closure =
-      base::MessageLoop::current()->QuitWhenIdleClosure();
+      base::MessageLoopCurrent::Get()->QuitWhenIdleClosure();
   closure_ = base::Bind(&QuitClosure::PostClosure, task_runner, quit_closure);
   cond_var_.Signal();
 }
@@ -428,7 +428,7 @@ void ChildThreadImpl::Init(const Options& options) {
   TRACE_EVENT0("startup", "ChildThreadImpl::Init");
   g_lazy_tls.Pointer()->Set(this);
   on_channel_error_called_ = false;
-  message_loop_ = base::MessageLoop::current();
+  main_thread_runner_ = base::ThreadTaskRunnerHandle::Get();
 #if BUILDFLAG(IPC_MESSAGE_LOG_ENABLED)
   // We must make sure to instantiate the IPC Logger *before* we create the
   // channel, otherwise we can get a callback on the IO thread which creates
@@ -472,8 +472,8 @@ void ChildThreadImpl::Init(const Options& options) {
   }
 
   sync_message_filter_ = channel_->CreateSyncMessageFilter();
-  thread_safe_sender_ = new ThreadSafeSender(
-      message_loop_->task_runner(), sync_message_filter_.get());
+  thread_safe_sender_ =
+      new ThreadSafeSender(main_thread_runner_, sync_message_filter_.get());
 
   auto registry = std::make_unique<service_manager::BinderRegistry>();
   registry->AddInterface(base::Bind(&ChildHistogramFetcherFactoryImpl::Create),
@@ -558,7 +558,7 @@ void ChildThreadImpl::Init(const Options& options) {
       connection_timeout = temp;
   }
 
-  message_loop_->task_runner()->PostDelayedTask(
+  main_thread_runner_->PostDelayedTask(
       FROM_HERE,
       base::BindOnce(&ChildThreadImpl::EnsureConnected,
                      channel_connected_factory_->GetWeakPtr()),
@@ -641,7 +641,7 @@ void ChildThreadImpl::OnChannelError() {
 }
 
 bool ChildThreadImpl::Send(IPC::Message* msg) {
-  DCHECK(message_loop_->task_runner()->BelongsToCurrentThread());
+  DCHECK(main_thread_runner_->BelongsToCurrentThread());
   if (!channel_) {
     delete msg;
     return false;
@@ -701,7 +701,7 @@ service_manager::Connector* ChildThreadImpl::GetConnector() {
 }
 
 IPC::MessageRouter* ChildThreadImpl::GetRouter() {
-  DCHECK(message_loop_->task_runner()->BelongsToCurrentThread());
+  DCHECK(main_thread_runner_->BelongsToCurrentThread());
   return &router_;
 }
 

content/child/child_thread_impl.h

@@ -12,6 +12,7 @@
 #include <string>
 
 #include "base/macros.h"
+#include "base/memory/scoped_refptr.h"
 #include "base/memory/shared_memory.h"
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/field_trial.h"
@@ -37,10 +38,6 @@
 #include "content/common/font_loader_mac.mojom.h"
 #endif
 
-namespace base {
-class MessageLoop;
-}  // namespace base
-
 namespace IPC {
 class MessageFilter;
 class SyncChannel;
@@ -132,7 +129,9 @@ class CONTENT_EXPORT ChildThreadImpl
     return thread_safe_sender_.get();
   }
 
-  base::MessageLoop* message_loop() const { return message_loop_; }
+  scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner() const {
+    return main_thread_runner_;
+  }
 
   // Returns the one child thread. Can only be called on the main thread.
   static ChildThreadImpl* current();
@@ -248,7 +247,8 @@ class CONTENT_EXPORT ChildThreadImpl
   // attempt to communicate.
   bool on_channel_error_called_;
 
-  base::MessageLoop* message_loop_;
+  // TaskRunner to post tasks to the main thread.
+  scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner_;
 
   std::unique_ptr<base::PowerMonitor> power_monitor_;
 

content/ppapi_plugin/ppapi_thread.cc

@@ -148,7 +148,7 @@ void PpapiThread::Shutdown() {
 
 bool PpapiThread::Send(IPC::Message* msg) {
   // Allow access from multiple threads.
-  if (message_loop()->task_runner()->BelongsToCurrentThread())
+  if (main_thread_runner()->BelongsToCurrentThread())
     return ChildThreadImpl::Send(msg);
 
   return sync_message_filter()->Send(msg);

content/renderer/render_thread_impl.cc

@@ -801,7 +801,7 @@ void RenderThreadImpl::Init(
 
   metrics::InitializeSingleSampleMetricsFactory(
       base::BindRepeating(&CreateSingleSampleMetricsProvider,
-                          message_loop()->task_runner(), GetConnector()));
+                          main_thread_runner(), GetConnector()));
 
   gpu_ = ui::Gpu::Create(GetConnector(),
                          base::FeatureList::IsEnabled(features::kMash)
@@ -853,14 +853,13 @@ void RenderThreadImpl::Init(
   peer_connection_factory_.reset(
       new PeerConnectionDependencyFactory(p2p_socket_dispatcher_.get()));
 
-  aec_dump_message_filter_ = new AecDumpMessageFilter(
-      GetIOTaskRunner(), message_loop()->task_runner());
+  aec_dump_message_filter_ =
+      new AecDumpMessageFilter(GetIOTaskRunner(), main_thread_runner());
 
   AddFilter(aec_dump_message_filter_.get());
 
 #endif  // BUILDFLAG(ENABLE_WEBRTC)
-  audio_input_ipc_factory_.emplace(message_loop()->task_runner(),
-                                   GetIOTaskRunner());
+  audio_input_ipc_factory_.emplace(main_thread_runner(), GetIOTaskRunner());
 
   audio_output_ipc_factory_.emplace(GetIOTaskRunner());
 
@@ -2397,7 +2396,7 @@ void RenderThreadImpl::RecordPurgeMemory(RendererMemoryMetrics before) {
 
 scoped_refptr<base::SingleThreadTaskRunner>
 RenderThreadImpl::GetMediaThreadTaskRunner() {
-  DCHECK(message_loop()->task_runner()->BelongsToCurrentThread());
+  DCHECK(main_thread_runner()->BelongsToCurrentThread());
   if (!media_thread_) {
     media_thread_.reset(new base::Thread("Media"));
     media_thread_->Start();