[EasyUnlock] Observe proximity changes and clean up TX power strategy.

components/proximity_auth/proximity_monitor_impl_unittest.cc

 // Copyright 2015 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 "components/proximity_auth/proximity_monitor_impl.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/macros.h"
@@ skipping 20 matching lines @@
 using testing::SaveArg;
 
 namespace proximity_auth {
 namespace {
 
 const char kRemoteDeviceUserId[] = "example@gmail.com";
 const char kRemoteDevicePublicKey[] = "Remote Public Key";
 const char kRemoteDeviceName[] = "LGE Nexus 5";
 const char kBluetoothAddress[] = "AA:BB:CC:DD:EE:FF";
 const char kPersistentSymmetricKey[] = "PSK";
-const int kRssiThreshold = -45;
+const int kRssiThreshold = -50;
 
 class MockProximityMonitorObserver : public ProximityMonitorObserver {
  public:
   MockProximityMonitorObserver() {}
   ~MockProximityMonitorObserver() override {}
 
   MOCK_METHOD0(OnProximityStateChanged, void());
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockProximityMonitorObserver);
@@ skipping 296 matching lines @@
   base::HistogramTester histogram_tester;
   monitor.RecordProximityMetricsOnAuthSuccess();
   histogram_tester.ExpectUniqueSample("EasyUnlock.AuthProximity.RollingRssi",
                                       127, 1);
   histogram_tester.ExpectUniqueSample(
       "EasyUnlock.AuthProximity.RemoteDeviceModelHash",
       -1808066424 /* hash of "Unknown" */, 1);
 }
 
 }  // namespace proximity_auth