[Remoting Mobile] Remove unused weak_ptr from ChromotingSession

The weak_ptr_ in ChromotingSession seems to be unused. This CL removes
it.

Bug: 817566
Change-Id: I4f07be8e8047b76ce36f5fe658b17bf6cf45ec72
Reviewed-on: https://chromium-review.googlesource.com/974563Reviewed-by: Joe Downing <joedow@chromium.org>
Commit-Queue: Yuwei Huang <yuweih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544956}

remoting/client/chromoting_session.cc

@@ -526,8 +526,7 @@ ChromotingSession::ChromotingSession(
     std::unique_ptr<protocol::VideoRenderer> video_renderer,
     base::WeakPtr<protocol::AudioStub> audio_player,
     const ConnectToHostInfo& info,
-    const protocol::ClientAuthenticationConfig& client_auth_config)
-    : weak_factory_(this) {
+    const protocol::ClientAuthenticationConfig& client_auth_config) {
   DCHECK(delegate);
   DCHECK(cursor_shape_stub);
   DCHECK(video_renderer);
@@ -535,7 +534,6 @@ ChromotingSession::ChromotingSession(
 
   runtime_ = ChromotingClientRuntime::GetInstance();
   DCHECK(runtime_->ui_task_runner()->BelongsToCurrentThread());
-  weak_ptr_ = weak_factory_.GetWeakPtr();
 
   logger_ = std::make_unique<ClientTelemetryLogger>(
       runtime_->log_writer(), ChromotingEvent::Mode::ME2ME);

remoting/client/chromoting_session.h

@@ -160,10 +160,6 @@ class ChromotingSession : public ClientInputInjector {
   // |core_| to allow accessing logs after |core_| becomes invalid.
   std::unique_ptr<ClientTelemetryLogger> logger_;
 
-  // This is bound to UI thread.
-  base::WeakPtr<ChromotingSession> weak_ptr_;
-  base::WeakPtrFactory<ChromotingSession> weak_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(ChromotingSession);
 };