[Sync] Refactoring of sync integration test checkers to remove boilerplate await methods.

chrome/browser/sync/test/integration/status_change_checker.cc

 // Copyright 2013 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 "chrome/browser/sync/test/integration/status_change_checker.h"
 
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/timer/timer.h"
 
-StatusChangeChecker::StatusChangeChecker() : timed_out_(false) {
-}
+StatusChangeChecker::StatusChangeChecker() : timed_out_(false) {}
 
 StatusChangeChecker::~StatusChangeChecker() {}
 
+bool StatusChangeChecker::Wait() {
+  if (IsExitConditionSatisfied()) {
+    DVLOG(1) << "Already satisfied: " << GetDebugMessage();
+  } else {
+    DVLOG(1) << "Blocking: " << GetDebugMessage();
+    StartBlockingWait();
+  }
+  return !TimedOut();
+}
+
 bool StatusChangeChecker::TimedOut() const {
   return timed_out_;
 }
 
 base::TimeDelta StatusChangeChecker::GetTimeoutDuration() {
   return base::TimeDelta::FromSeconds(45);
 }
 
 void StatusChangeChecker::StartBlockingWait() {
   base::OneShotTimer timer;
@@ skipping 19 matching lines @@
     DVLOG(1) << "Await -> Condition met: " << GetDebugMessage();
     StopWaiting();
   }
 }
 
 void StatusChangeChecker::OnTimeout() {
   DVLOG(1) << "Await -> Timed out: " << GetDebugMessage();
   timed_out_ = true;
   StopWaiting();
 }