Change other usages of .size() to .empty() when applicable.

chrome/browser/automation/automation_provider_observers.cc

 // Copyright (c) 2011 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/automation/automation_provider_observers.h"
 
 #include <deque>
 #include <string>
 #include <vector>
 
@@ skipping 609 matching lines @@
       NOTREACHED();
   }
   // There may be a reply message waiting for this event, so check.
   MaybeSendResult();
 }
 
 void ExtensionTestResultNotificationObserver::MaybeSendResult() {
   if (!automation_)
     return;
 
-  if (results_.size() > 0) {
+  if (!results_.empty()) {
     // This release method should return the automation's current
     // reply message, or NULL if there is no current one. If it is not
     // NULL, we are stating that we will handle this reply message.
     IPC::Message* reply_message = automation_->reply_message_release();
     // Send the result back if we have a reply message.
     if (reply_message) {
       AutomationMsg_WaitForExtensionTestResult::WriteReplyParams(
           reply_message, results_.front(), messages_.front());
       results_.pop_front();
       messages_.pop_front();
@@ skipping 1438 matching lines @@
       NewRunnableMethod(
           this,
           &WaitForProcessLauncherThreadToGoIdleObserver::RunOnUIThread));
 }
 
 void WaitForProcessLauncherThreadToGoIdleObserver::RunOnUIThread() {
   if (automation_)
     automation_->Send(reply_message_.release());
   Release();
 }