Add a new GetInstance() method for singleton classes under chrome/service and /net.

This is a small step towards making all singleton classes use the Singleton<T> pattern within their code and not expect the callers to know about it.

This CL includes files under chrome/service and /net with related files elsewhere.

Suggested files to focus for reviewers:
- @sanjeevr for chrome/common and chrome/service
- @ukai for net/websockets
- @agl for rest of net

BUG=65298
TEST=all existing tests should continue to pass.

Review URL: http://codereview.chromium.org/5634005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@68722 0039d316-1c4b-4281-b951-d872f2087c98

17 files changed, 97 insertions, 43 deletions

diff --git a/net/base/bandwidth_metrics.cc b/net/base/bandwidth_metrics.cc
new file mode 100644
index 0000000..eaaa3c0
--- /dev/null
+++ b/net/base/bandwidth_metrics.cc
@@ -0,0 +1,15 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/singleton.h"
+#include "net/base/bandwidth_metrics.h"
+
+namespace net {
+
+ScopedBandwidthMetrics::ScopedBandwidthMetrics()
+    : metrics_(Singleton<BandwidthMetrics>::get()),
+      started_(false) {
+}
+
+}  // namespace net
diff --git a/net/base/bandwidth_metrics.h b/net/base/bandwidth_metrics.h
index 80fa005..aef366d 100644
--- a/net/base/bandwidth_metrics.h
+++ b/net/base/bandwidth_metrics.h
@@ -121,9 +121,7 @@ class BandwidthMetrics {
 // ensure we always stop them.
 class ScopedBandwidthMetrics {
  public:
-  explicit ScopedBandwidthMetrics(BandwidthMetrics* metrics)
-      : metrics_(metrics), started_(false) {
-  }
+  ScopedBandwidthMetrics();
 
   ~ScopedBandwidthMetrics() {
     if (started_)
diff --git a/net/net.gyp b/net/net.gyp
index 447c4f6..82359ab 100644
--- a/net/net.gyp
+++ b/net/net.gyp
@@ -29,6 +29,8 @@
         'base/address_list_net_log_param.h',
         'base/auth.cc',
         'base/auth.h',
+        'base/bandwidth_metrics.cc',
+        'base/bandwidth_metrics.h',
         'base/cache_type.h',
         'base/capturing_net_log.cc',
         'base/capturing_net_log.h',
diff --git a/net/socket_stream/socket_stream_job.cc b/net/socket_stream/socket_stream_job.cc
index 8d1da73..6636233 100644
--- a/net/socket_stream/socket_stream_job.cc
+++ b/net/socket_stream/socket_stream_job.cc
@@ -9,20 +9,17 @@
 
 namespace net {
 
-static SocketStreamJobManager* GetJobManager() {
-  return Singleton<SocketStreamJobManager>::get();
-}
-
 // static
 SocketStreamJob::ProtocolFactory* SocketStreamJob::RegisterProtocolFactory(
     const std::string& scheme, ProtocolFactory* factory) {
-  return GetJobManager()->RegisterProtocolFactory(scheme, factory);
+  return SocketStreamJobManager::GetInstance()->RegisterProtocolFactory(
+      scheme, factory);
 }
 
 // static
 SocketStreamJob* SocketStreamJob::CreateSocketStreamJob(
     const GURL& url, SocketStream::Delegate* delegate) {
-  return GetJobManager()->CreateJob(url, delegate);
+  return SocketStreamJobManager::GetInstance()->CreateJob(url, delegate);
 }
 
 SocketStreamJob::SocketStreamJob() {}
diff --git a/net/socket_stream/socket_stream_job_manager.cc b/net/socket_stream/socket_stream_job_manager.cc
index 7dd0d6b..de2f0a8 100644
--- a/net/socket_stream/socket_stream_job_manager.cc
+++ b/net/socket_stream/socket_stream_job_manager.cc
@@ -4,6 +4,8 @@
 
 #include "net/socket_stream/socket_stream_job_manager.h"
 
+#include "base/singleton.h"
+
 namespace net {
 
 SocketStreamJobManager::SocketStreamJobManager() {
@@ -12,6 +14,11 @@ SocketStreamJobManager::SocketStreamJobManager() {
 SocketStreamJobManager::~SocketStreamJobManager() {
 }
 
+// static
+SocketStreamJobManager* SocketStreamJobManager::GetInstance() {
+  return Singleton<SocketStreamJobManager>::get();
+}
+
 SocketStreamJob* SocketStreamJobManager::CreateJob(
     const GURL& url, SocketStream::Delegate* delegate) const {
   // If url is invalid, create plain SocketStreamJob, which will close
diff --git a/net/socket_stream/socket_stream_job_manager.h b/net/socket_stream/socket_stream_job_manager.h
index 1150058..fbd572d 100644
--- a/net/socket_stream/socket_stream_job_manager.h
+++ b/net/socket_stream/socket_stream_job_manager.h
@@ -12,14 +12,15 @@
 #include "net/socket_stream/socket_stream.h"
 #include "net/socket_stream/socket_stream_job.h"
 
+template <typename T> struct DefaultSingletonTraits;
 class GURL;
 
 namespace net {
 
 class SocketStreamJobManager {
  public:
-  SocketStreamJobManager();
-  ~SocketStreamJobManager();
+  // Returns the singleton instance.
+  static SocketStreamJobManager* GetInstance();
 
   SocketStreamJob* CreateJob(
       const GURL& url, SocketStream::Delegate* delegate) const;
@@ -28,8 +29,12 @@ class SocketStreamJobManager {
       const std::string& scheme, SocketStreamJob::ProtocolFactory* factory);
 
  private:
+  friend struct DefaultSingletonTraits<SocketStreamJobManager>;
   typedef std::map<std::string, SocketStreamJob::ProtocolFactory*> FactoryMap;
 
+  SocketStreamJobManager();
+  ~SocketStreamJobManager();
+
   mutable Lock lock_;
   FactoryMap factories_;
 
diff --git a/net/spdy/spdy_stream.cc b/net/spdy/spdy_stream.cc
index 8a5d4a4..3900993 100644
--- a/net/spdy/spdy_stream.cc
+++ b/net/spdy/spdy_stream.cc
@@ -6,7 +6,6 @@
 
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/singleton.h"
 #include "base/values.h"
 #include "net/spdy/spdy_session.h"
 
@@ -47,7 +46,6 @@ SpdyStream::SpdyStream(SpdySession* session,
       send_window_size_(spdy::kSpdyStreamInitialWindowSize),
       recv_window_size_(spdy::kSpdyStreamInitialWindowSize),
       pushed_(pushed),
-      metrics_(Singleton<BandwidthMetrics>::get()),
       response_received_(false),
       session_(session),
       delegate_(NULL),
diff --git a/net/url_request/https_prober.cc b/net/url_request/https_prober.cc
index 4388294..bdafcf6 100644
--- a/net/url_request/https_prober.cc
+++ b/net/url_request/https_prober.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/singleton.h"
 #include "net/url_request/https_prober.h"
 
 #include "net/url_request/url_request.h"
@@ -15,6 +16,11 @@ HTTPSProber::HTTPSProber() {
 HTTPSProber::~HTTPSProber() {
 }
 
+// static
+HTTPSProber* HTTPSProber::GetInstance() {
+  return Singleton<HTTPSProber>::get();
+}
+
 bool HTTPSProber::HaveProbed(const std::string& host) const {
   return probed_.find(host) != probed_.end();
 }
diff --git a/net/url_request/https_prober.h b/net/url_request/https_prober.h
index 1667911..5d1a6222 100644
--- a/net/url_request/https_prober.h
+++ b/net/url_request/https_prober.h
@@ -10,10 +10,10 @@
 #include <set>
 #include <string>
 
-#include "base/singleton.h"
 #include "base/task.h"
 #include "net/url_request/url_request.h"
 
+template <typename T> struct DefaultSingletonTraits;
 class URLRequestContext;
 
 namespace net {
@@ -33,8 +33,8 @@ class HTTPSProberDelegate {
 // transparently upgrading from HTTP to HTTPS (for example, for SPDY).
 class HTTPSProber : public net::URLRequest::Delegate {
  public:
-  HTTPSProber();
-  ~HTTPSProber();
+  // Returns the singleton instance.
+  static HTTPSProber* GetInstance();
 
   // HaveProbed returns true if the given host is known to have been probed
   // since the browser was last started.
@@ -62,6 +62,9 @@ class HTTPSProber : public net::URLRequest::Delegate {
   virtual void OnReadCompleted(net::URLRequest* request, int bytes_read);
 
  private:
+  HTTPSProber();
+  ~HTTPSProber();
+
   void Success(net::URLRequest* request);
   void Failure(net::URLRequest* request);
   void DoCallback(net::URLRequest* request, bool result);
diff --git a/net/url_request/url_request.cc b/net/url_request/url_request.cc
index b71e764..26a9da2 100644
--- a/net/url_request/url_request.cc
+++ b/net/url_request/url_request.cc
@@ -29,10 +29,6 @@ namespace {
 // Max number of http redirects to follow.  Same number as gecko.
 const int kMaxRedirects = 20;
 
-URLRequestJobManager* GetJobManager() {
-  return Singleton<URLRequestJobManager>::get();
-}
-
 // Discard headers which have meaning in POST (Content-Length, Content-Type,
 // Origin).
 void StripPostSpecificHeaders(net::HttpRequestHeaders* headers) {
@@ -130,17 +126,19 @@ URLRequest::~URLRequest() {
 // static
 URLRequest::ProtocolFactory* URLRequest::RegisterProtocolFactory(
     const string& scheme, ProtocolFactory* factory) {
-  return GetJobManager()->RegisterProtocolFactory(scheme, factory);
+  return URLRequestJobManager::GetInstance()->RegisterProtocolFactory(scheme,
+                                                                      factory);
 }
 
 // static
 void URLRequest::RegisterRequestInterceptor(Interceptor* interceptor) {
-  GetJobManager()->RegisterRequestInterceptor(interceptor);
+  URLRequestJobManager::GetInstance()->RegisterRequestInterceptor(interceptor);
 }
 
 // static
 void URLRequest::UnregisterRequestInterceptor(Interceptor* interceptor) {
-  GetJobManager()->UnregisterRequestInterceptor(interceptor);
+  URLRequestJobManager::GetInstance()->UnregisterRequestInterceptor(
+      interceptor);
 }
 
 void URLRequest::AppendBytesToUpload(const char* bytes, int bytes_len) {
@@ -264,7 +262,7 @@ int URLRequest::GetResponseCode() {
 
 // static
 bool URLRequest::IsHandledProtocol(const std::string& scheme) {
-  return GetJobManager()->SupportsScheme(scheme);
+  return URLRequestJobManager::GetInstance()->SupportsScheme(scheme);
 }
 
 // static
@@ -279,12 +277,12 @@ bool URLRequest::IsHandledURL(const GURL& url) {
 
 // static
 void URLRequest::AllowFileAccess() {
-  GetJobManager()->set_enable_file_access(true);
+  URLRequestJobManager::GetInstance()->set_enable_file_access(true);
 }
 
 // static
 bool URLRequest::IsFileAccessAllowed() {
-  return GetJobManager()->enable_file_access();
+  return URLRequestJobManager::GetInstance()->enable_file_access();
 }
 
 
@@ -318,7 +316,7 @@ GURL URLRequest::GetSanitizedReferrer() const {
 }
 
 void URLRequest::Start() {
-  StartJob(GetJobManager()->CreateJob(this));
+  StartJob(URLRequestJobManager::GetInstance()->CreateJob(this));
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -353,7 +351,7 @@ void URLRequest::StartJob(URLRequestJob* job) {
 void URLRequest::Restart() {
   // Should only be called if the original job didn't make any progress.
   DCHECK(job_ && !job_->has_response_started());
-  RestartWithJob(GetJobManager()->CreateJob(this));
+  RestartWithJob(URLRequestJobManager::GetInstance()->CreateJob(this));
 }
 
 void URLRequest::RestartWithJob(URLRequestJob *job) {
@@ -427,7 +425,9 @@ void URLRequest::StopCaching() {
 }
 
 void URLRequest::ReceivedRedirect(const GURL& location, bool* defer_redirect) {
-  URLRequestJob* job = GetJobManager()->MaybeInterceptRedirect(this, location);
+  URLRequestJob* job =
+      URLRequestJobManager::GetInstance()->MaybeInterceptRedirect(this,
+                                                                  location);
   if (job) {
     RestartWithJob(job);
   } else if (delegate_) {
@@ -441,7 +441,8 @@ void URLRequest::ResponseStarted() {
     params = new net::NetLogIntegerParameter("net_error", status_.os_error());
   net_log_.EndEvent(net::NetLog::TYPE_URL_REQUEST_START_JOB, params);
 
-  URLRequestJob* job = GetJobManager()->MaybeInterceptResponse(this);
+  URLRequestJob* job =
+      URLRequestJobManager::GetInstance()->MaybeInterceptResponse(this);
   if (job) {
     RestartWithJob(job);
   } else if (delegate_) {
diff --git a/net/url_request/url_request_http_job.cc b/net/url_request/url_request_http_job.cc
index c951088..f2b1b4f 100644
--- a/net/url_request/url_request_http_job.cc
+++ b/net/url_request/url_request_http_job.cc
@@ -937,7 +937,7 @@ void URLRequestHttpJob::ProcessStrictTransportSecurityHeader() {
     // At this point, we have a request for opportunistic encryption over HTTP.
     // In this case we need to probe to check that we can make HTTPS
     // connections to that host.
-    net::HTTPSProber* const prober = Singleton<net::HTTPSProber>::get();
+    net::HTTPSProber* const prober = net::HTTPSProber::GetInstance();
     if (prober->HaveProbed(request_info_.url.host()) ||
         prober->InFlight(request_info_.url.host())) {
       continue;
diff --git a/net/url_request/url_request_job_manager.cc b/net/url_request/url_request_job_manager.cc
index 1bc0be1..117c15a 100644
--- a/net/url_request/url_request_job_manager.cc
+++ b/net/url_request/url_request_job_manager.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 
 #include "build/build_config.h"
+#include "base/singleton.h"
 #include "base/string_util.h"
 #include "net/base/load_flags.h"
 #include "net/base/net_errors.h"
@@ -45,6 +46,11 @@ URLRequestJobManager::URLRequestJobManager() : enable_file_access_(false) {
 
 URLRequestJobManager::~URLRequestJobManager() {}
 
+// static
+URLRequestJobManager* URLRequestJobManager::GetInstance() {
+  return Singleton<URLRequestJobManager>::get();
+}
+
 URLRequestJob* URLRequestJobManager::CreateJob(net::URLRequest* request) const {
 #ifndef NDEBUG
   DCHECK(IsAllowedThread());
diff --git a/net/url_request/url_request_job_manager.h b/net/url_request/url_request_job_manager.h
index 6d2421a..1e56b12 100644
--- a/net/url_request/url_request_job_manager.h
+++ b/net/url_request/url_request_job_manager.h
@@ -14,6 +14,8 @@
 #include "base/platform_thread.h"
 #include "net/url_request/url_request.h"
 
+template <typename T> struct DefaultSingletonTraits;
+
 // This class is responsible for managing the set of protocol factories and
 // request interceptors that determine how an URLRequestJob gets created to
 // handle an net::URLRequest.
@@ -27,8 +29,8 @@
 //
 class URLRequestJobManager {
  public:
-  URLRequestJobManager();
-  ~URLRequestJobManager();
+  // Returns the singleton instance.
+  static URLRequestJobManager* GetInstance();
 
   // Instantiate an URLRequestJob implementation based on the registered
   // interceptors and protocol factories.  This will always succeed in
@@ -67,6 +69,10 @@ class URLRequestJobManager {
  private:
   typedef std::map<std::string, net::URLRequest::ProtocolFactory*> FactoryMap;
   typedef std::vector<net::URLRequest::Interceptor*> InterceptorList;
+  friend struct DefaultSingletonTraits<URLRequestJobManager>;
+
+  URLRequestJobManager();
+  ~URLRequestJobManager();
 
   mutable Lock lock_;
   FactoryMap factories_;
diff --git a/net/websockets/websocket_job.cc b/net/websockets/websocket_job.cc
index a1e2dde..9adbaa3 100644
--- a/net/websockets/websocket_job.cc
+++ b/net/websockets/websocket_job.cc
@@ -6,6 +6,7 @@
 
 #include <algorithm>
 
+#include "base/singleton.h"
 #include "base/string_tokenizer.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/net_errors.h"
@@ -144,8 +145,8 @@ void WebSocketJob::RestartWithAuth(
 
 void WebSocketJob::DetachDelegate() {
   state_ = CLOSED;
-  Singleton<WebSocketThrottle>::get()->RemoveFromQueue(this);
-  Singleton<WebSocketThrottle>::get()->WakeupSocketIfNecessary();
+  WebSocketThrottle::GetInstance()->RemoveFromQueue(this);
+  WebSocketThrottle::GetInstance()->WakeupSocketIfNecessary();
 
   scoped_refptr<WebSocketJob> protect(this);
 
@@ -165,7 +166,7 @@ int WebSocketJob::OnStartOpenConnection(
   DCHECK(!callback_);
   state_ = CONNECTING;
   addresses_.Copy(socket->address_list().head(), true);
-  Singleton<WebSocketThrottle>::get()->PutInQueue(this);
+  WebSocketThrottle::GetInstance()->PutInQueue(this);
   if (!waiting_)
     return OK;
   callback_ = callback;
@@ -237,8 +238,8 @@ void WebSocketJob::OnReceivedData(
 
 void WebSocketJob::OnClose(SocketStream* socket) {
   state_ = CLOSED;
-  Singleton<WebSocketThrottle>::get()->RemoveFromQueue(this);
-  Singleton<WebSocketThrottle>::get()->WakeupSocketIfNecessary();
+  WebSocketThrottle::GetInstance()->RemoveFromQueue(this);
+  WebSocketThrottle::GetInstance()->WakeupSocketIfNecessary();
 
   scoped_refptr<WebSocketJob> protect(this);
 
@@ -405,8 +406,8 @@ void WebSocketJob::SaveNextCookie() {
 
     handshake_response_.reset();
 
-    Singleton<WebSocketThrottle>::get()->RemoveFromQueue(this);
-    Singleton<WebSocketThrottle>::get()->WakeupSocketIfNecessary();
+    WebSocketThrottle::GetInstance()->RemoveFromQueue(this);
+    WebSocketThrottle::GetInstance()->WakeupSocketIfNecessary();
     return;
   }
 
diff --git a/net/websockets/websocket_job_unittest.cc b/net/websockets/websocket_job_unittest.cc
index 53d4a625..43d8509 100644
--- a/net/websockets/websocket_job_unittest.cc
+++ b/net/websockets/websocket_job_unittest.cc
@@ -222,7 +222,7 @@ class WebSocketJobTest : public PlatformTest {
     addr.ai_addr = reinterpret_cast<sockaddr*>(&sa_in);
     addr.ai_next = NULL;
     websocket_->addresses_.Copy(&addr, true);
-    Singleton<WebSocketThrottle>::get()->PutInQueue(websocket_);
+    WebSocketThrottle::GetInstance()->PutInQueue(websocket_);
   }
   WebSocketJob::State GetWebSocketJobState() {
     return websocket_->state_;
@@ -230,7 +230,7 @@ class WebSocketJobTest : public PlatformTest {
   void CloseWebSocketJob() {
     if (websocket_->socket_) {
       websocket_->socket_->DetachDelegate();
-      Singleton<WebSocketThrottle>::get()->RemoveFromQueue(websocket_);
+      WebSocketThrottle::GetInstance()->RemoveFromQueue(websocket_);
     }
     websocket_->state_ = WebSocketJob::CLOSED;
     websocket_->delegate_ = NULL;
diff --git a/net/websockets/websocket_throttle.cc b/net/websockets/websocket_throttle.cc
index 2d62815..c714de6 100644
--- a/net/websockets/websocket_throttle.cc
+++ b/net/websockets/websocket_throttle.cc
@@ -54,6 +54,11 @@ WebSocketThrottle::~WebSocketThrottle() {
   DCHECK(addr_map_.empty());
 }
 
+// static
+WebSocketThrottle* WebSocketThrottle::GetInstance() {
+  return Singleton<WebSocketThrottle>::get();
+}
+
 void WebSocketThrottle::PutInQueue(WebSocketJob* job) {
   queue_.push_back(job);
   const AddressList& address_list = job->address_list();
diff --git a/net/websockets/websocket_throttle.h b/net/websockets/websocket_throttle.h
index 0849834..9becc62 100644
--- a/net/websockets/websocket_throttle.h
+++ b/net/websockets/websocket_throttle.h
@@ -10,7 +10,8 @@
 #include <string>
 
 #include "base/hash_tables.h"
-#include "base/singleton.h"
+
+template <typename T> struct DefaultSingletonTraits;
 
 namespace net {
 
@@ -27,6 +28,9 @@ class WebSocketJob;
 //        for that connection to have failed.
 class WebSocketThrottle {
  public:
+  // Returns the singleton instance.
+  static WebSocketThrottle* GetInstance();
+
   // Puts |job| in |queue_| and queues for the destination addresses
   // of |job|.
   // If other job is using the same destination address, set |job| waiting.