(Tiny) Make some execution_phase.cc includes windows only

components/metrics/execution_phase.cc

 // Copyright 2017 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/metrics/execution_phase.h"
 
 #include "build/build_config.h"
-#include "components/browser_watcher/stability_data_names.h"
-#include "components/browser_watcher/stability_debugging.h"
 #include "components/metrics/metrics_pref_names.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
 
+#if defined(OS_WIN)
+#include "components/browser_watcher/stability_data_names.h"
+#include "components/browser_watcher/stability_debugging.h"
+#endif  // defined(OS_WIN)
+
 namespace metrics {
 
 ExecutionPhaseManager::ExecutionPhaseManager(PrefService* local_state)
     : local_state_(local_state) {}
 
 ExecutionPhaseManager::~ExecutionPhaseManager() {}
 
 // static
 void ExecutionPhaseManager::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterIntegerPref(
@@ skipping 33 matching lines @@
 }
 
 void ExecutionPhaseManager::OnAppEnterForeground() {
   // Restore prefs value altered by OnEnterBackground.
   local_state_->SetInteger(prefs::kStabilityExecutionPhase,
                            static_cast<int>(execution_phase_));
 }
 #endif  // defined(OS_ANDROID) || defined(OS_IOS)
 
 }  // namespace metrics