Rename HidServiceLinux and HidConnectionLinux helper classes.

This change documents that these helper classes live on the FILE thread
by naming them HidServiceLinux::FileThreadHelper and
HidConnectionLinux::FileThreadHelper.

BUG=

Review URL: https://codereview.chromium.org/851543002

Cr-Commit-Position: refs/heads/master@{#311120}

4 files changed, 27 insertions, 23 deletions

diff --git a/device/hid/hid_connection_linux.cc b/device/hid/hid_connection_linux.cc
index e9ca4b2..c653f4b 100644
--- a/device/hid/hid_connection_linux.cc
+++ b/device/hid/hid_connection_linux.cc
@@ -29,12 +29,13 @@
 
 namespace device {
 
-class HidConnectionLinux::Helper : public base::MessagePumpLibevent::Watcher {
+class HidConnectionLinux::FileThreadHelper
+    : public base::MessagePumpLibevent::Watcher {
  public:
-  Helper(base::PlatformFile platform_file,
-         scoped_refptr<HidDeviceInfo> device_info,
-         base::WeakPtr<HidConnectionLinux> connection,
-         scoped_refptr<base::SingleThreadTaskRunner> task_runner)
+  FileThreadHelper(base::PlatformFile platform_file,
+                   scoped_refptr<HidDeviceInfo> device_info,
+                   base::WeakPtr<HidConnectionLinux> connection,
+                   scoped_refptr<base::SingleThreadTaskRunner> task_runner)
       : platform_file_(platform_file),
         connection_(connection),
         task_runner_(task_runner) {
@@ -43,7 +44,9 @@ class HidConnectionLinux::Helper : public base::MessagePumpLibevent::Watcher {
     has_report_id_ = device_info->has_report_id();
   }
 
-  ~Helper() override { DCHECK(thread_checker_.CalledOnValidThread()); }
+  ~FileThreadHelper() override {
+    DCHECK(thread_checker_.CalledOnValidThread());
+  }
 
   // Starts the FileDescriptorWatcher that reads input events from the device.
   // Must be called on a thread that has a base::MessageLoopForIO. The helper
@@ -122,10 +125,10 @@ HidConnectionLinux::HidConnectionLinux(
 
   // The helper is passed a weak pointer to this connection so that it can be
   // cleaned up after the connection is closed.
-  helper_ = new Helper(device_file_.GetPlatformFile(), device_info,
-                       weak_factory_.GetWeakPtr(), task_runner_);
-  file_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&Helper::Start, base::Unretained(helper_)));
+  helper_ = new FileThreadHelper(device_file_.GetPlatformFile(), device_info,
+                                 weak_factory_.GetWeakPtr(), task_runner_);
+  file_task_runner_->PostTask(FROM_HERE, base::Bind(&FileThreadHelper::Start,
+                                                    base::Unretained(helper_)));
 }
 
 HidConnectionLinux::~HidConnectionLinux() {
diff --git a/device/hid/hid_connection_linux.h b/device/hid/hid_connection_linux.h
index c8ffc85..1f32420 100644
--- a/device/hid/hid_connection_linux.h
+++ b/device/hid/hid_connection_linux.h
@@ -25,9 +25,8 @@ class HidConnectionLinux : public HidConnection {
       scoped_refptr<base::SingleThreadTaskRunner> file_thread_runner);
 
  private:
-  class Helper;
-  friend class Helper;
   friend class base::RefCountedThreadSafe<HidConnectionLinux>;
+  class FileThreadHelper;
 
   typedef base::Callback<void(ssize_t)> InternalWriteCallback;
   typedef base::Callback<void(int)> IoctlCallback;
@@ -78,7 +77,7 @@ class HidConnectionLinux : public HidConnection {
   void ProcessReadQueue();
 
   base::File device_file_;
-  Helper* helper_;
+  FileThreadHelper* helper_;
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
diff --git a/device/hid/hid_service_linux.cc b/device/hid/hid_service_linux.cc
index 556f3bb..052a5a2 100644
--- a/device/hid/hid_service_linux.cc
+++ b/device/hid/hid_service_linux.cc
@@ -60,22 +60,25 @@ struct HidServiceLinux::ConnectParams {
   base::File device_file;
 };
 
-class HidServiceLinux::Helper : public DeviceMonitorLinux::Observer,
-                                public base::MessageLoop::DestructionObserver {
+class HidServiceLinux::FileThreadHelper
+    : public DeviceMonitorLinux::Observer,
+      public base::MessageLoop::DestructionObserver {
  public:
-  Helper(base::WeakPtr<HidServiceLinux> service,
-         scoped_refptr<base::SingleThreadTaskRunner> task_runner)
+  FileThreadHelper(base::WeakPtr<HidServiceLinux> service,
+                   scoped_refptr<base::SingleThreadTaskRunner> task_runner)
       : observer_(this), service_(service), task_runner_(task_runner) {
     DeviceMonitorLinux* monitor = DeviceMonitorLinux::GetInstance();
     observer_.Add(monitor);
     monitor->Enumerate(
-        base::Bind(&Helper::OnDeviceAdded, base::Unretained(this)));
+        base::Bind(&FileThreadHelper::OnDeviceAdded, base::Unretained(this)));
     task_runner->PostTask(
         FROM_HERE,
         base::Bind(&HidServiceLinux::FirstEnumerationComplete, service_));
   }
 
-  ~Helper() override { DCHECK(thread_checker_.CalledOnValidThread()); }
+  ~FileThreadHelper() override {
+    DCHECK(thread_checker_.CalledOnValidThread());
+  }
 
  private:
   // DeviceMonitorLinux::Observer:
@@ -202,7 +205,7 @@ void HidServiceLinux::StartHelper(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   // Helper is a message loop destruction observer and will delete itself when
   // this thread's message loop is destroyed.
-  new Helper(weak_ptr, task_runner);
+  new FileThreadHelper(weak_ptr, task_runner);
 }
 
 void HidServiceLinux::Connect(const HidDeviceId& device_id,
diff --git a/device/hid/hid_service_linux.h b/device/hid/hid_service_linux.h
index fd833b6..3cb75c5 100644
--- a/device/hid/hid_service_linux.h
+++ b/device/hid/hid_service_linux.h
@@ -24,8 +24,7 @@ class HidServiceLinux : public HidService {
 
  private:
   struct ConnectParams;
-  class Helper;
-  friend class Helper;
+  class FileThreadHelper;
 
   ~HidServiceLinux() override;
 
@@ -50,7 +49,7 @@ class HidServiceLinux : public HidService {
 
   // The helper lives on the FILE thread and holds a weak reference back to the
   // service that owns it.
-  scoped_ptr<Helper> helper_;
+  scoped_ptr<FileThreadHelper> helper_;
   base::WeakPtrFactory<HidServiceLinux> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HidServiceLinux);