Reland "Reland "Replace the usage of MetricsObserverInterface by RTC_HISTOGRAM_*.""

This is a reland of 1a2cc0acba6a66f89249455d8e5775849b56f755

Original change's description:
> Reland "Replace the usage of MetricsObserverInterface by RTC_HISTOGRAM_*."
>
> This is a reland of 870bca1f418a1abf445169a638a61f9a649d557f
>
> Original change's description:
> > Replace the usage of MetricsObserverInterface by RTC_HISTOGRAM_*.
> >
> > We now use RTC_HISTOGRAM_* macros in system_wrappers/include/metrics.h
> > to report the metrics in pc/ and p2p/ that are currently been reported
> > using MetricsObserverInterface.
> >
> > TBR=tommi@webrtc.org
> >
> > Bug: webrtc:9409
> > Change-Id: I47c9975402293c72250203fa1ec19eb1668766f6
> > Reviewed-on: https://webrtc-review.googlesource.com/83782
> > Commit-Queue: Qingsi Wang <qingsi@google.com>
> > Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> > Reviewed-by: Taylor (left Google) <deadbeef@webrtc.org>
> > Reviewed-by: Steve Anton <steveanton@webrtc.org>
> > Cr-Commit-Position: refs/heads/master@{#23914}
>
> TBR=steveanton@webrtc.org,hta@webrtc.org,tommi@webrtc.org
>
> Bug: webrtc:9409
> Change-Id: I37fc95ced60dea25aa9b4f5ad44bdf7174c8bd5c
> Reviewed-on: https://webrtc-review.googlesource.com/88060
> Reviewed-by: Qingsi Wang <qingsi@webrtc.org>
> Commit-Queue: Qingsi Wang <qingsi@google.com>
> Cr-Commit-Position: refs/heads/master@{#23919}

TBR=steveanton@webrtc.org,tommi@webrtc.org

Bug: webrtc:9409
Change-Id: Ib55f0b6c9bcb9d9585924a4dfac5cf643ff4d76b
Reviewed-on: https://webrtc-review.googlesource.com/88343
Commit-Queue: Qingsi Wang <qingsi@google.com>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23957}

2 files changed, 23 insertions, 7 deletions

diff --git a/p2p/client/basicportallocator.cc b/p2p/client/basicportallocator.cc
index 4335ddaad4..eb14a37758 100644
--- a/p2p/client/basicportallocator.cc
+++ b/p2p/client/basicportallocator.cc
@@ -16,7 +16,6 @@
 #include <string>
 #include <vector>
 
-#include "api/umametrics.h"
 #include "p2p/base/basicpacketsocketfactory.h"
 #include "p2p/base/port.h"
 #include "p2p/base/relayport.h"
@@ -28,6 +27,7 @@
 #include "rtc_base/helpers.h"
 #include "rtc_base/ipaddress.h"
 #include "rtc_base/logging.h"
+#include "system_wrappers/include/metrics.h"
 
 using rtc::CreateRandomId;
 
@@ -196,9 +196,6 @@ void BasicPortAllocator::Construct() {
 
 void BasicPortAllocator::OnIceRegathering(PortAllocatorSession* session,
                                           IceRegatheringReason reason) {
-  if (!metrics_observer()) {
-    return;
-  }
   // If the session has not been taken by an active channel, do not report the
   // metric.
   for (auto& allocator_session : pooled_sessions()) {
@@ -207,9 +204,9 @@ void BasicPortAllocator::OnIceRegathering(PortAllocatorSession* session,
     }
   }
 
-  metrics_observer()->IncrementEnumCounter(
-      webrtc::kEnumCounterIceRegathering, static_cast<int>(reason),
-      static_cast<int>(IceRegatheringReason::MAX_VALUE));
+  RTC_HISTOGRAM_ENUMERATION("WebRTC.PeerConnection.IceRegatheringReason",
+                            static_cast<int>(reason),
+                            static_cast<int>(IceRegatheringReason::MAX_VALUE));
 }
 
 BasicPortAllocator::~BasicPortAllocator() {
diff --git a/p2p/client/basicportallocator_unittest.cc b/p2p/client/basicportallocator_unittest.cc
index d995eb18de..b3e52ffec5 100644
--- a/p2p/client/basicportallocator_unittest.cc
+++ b/p2p/client/basicportallocator_unittest.cc
@@ -34,6 +34,7 @@
 #include "rtc_base/ssladapter.h"
 #include "rtc_base/thread.h"
 #include "rtc_base/virtualsocketserver.h"
+#include "system_wrappers/include/metrics_default.h"
 
 using rtc::IPAddress;
 using rtc::SocketAddress;
@@ -168,6 +169,7 @@ class BasicPortAllocatorTestBase : public testing::Test,
                                             kRelaySslTcpIntAddr));
     allocator_->Initialize();
     allocator_->set_step_delay(kMinimumStepDelay);
+    webrtc::metrics::Reset();
   }
 
   void AddInterface(const SocketAddress& addr) {
@@ -2368,4 +2370,21 @@ TEST_F(BasicPortAllocatorTest,
                                             expected_stun_keepalive_interval);
 }
 
+TEST_F(BasicPortAllocatorTest, IceRegatheringMetricsLoggedWhenNetworkChanges) {
+  // Only test local ports to simplify test.
+  ResetWithNoServersOrNat();
+  AddInterface(kClientAddr, "test_net0");
+  ASSERT_TRUE(CreateSession(ICE_CANDIDATE_COMPONENT_RTP));
+  session_->StartGettingPorts();
+  EXPECT_TRUE_SIMULATED_WAIT(candidate_allocation_done_,
+                             kDefaultAllocationTimeout, fake_clock);
+  candidate_allocation_done_ = false;
+  AddInterface(kClientAddr2, "test_net1");
+  EXPECT_TRUE_SIMULATED_WAIT(candidate_allocation_done_,
+                             kDefaultAllocationTimeout, fake_clock);
+  EXPECT_EQ(1, webrtc::metrics::NumEvents(
+                   "WebRTC.PeerConnection.IceRegatheringReason",
+                   static_cast<int>(IceRegatheringReason::NETWORK_CHANGE)));
+}
+
 }  // namespace cricket