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

chrome/common/extensions/user_script.cc

 // Copyright (c) 2010 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/common/extensions/user_script.h"
 
 #include "base/pickle.h"
 #include "base/string_util.h"
 
 namespace {
@@ skipping 61 matching lines @@
 UserScript::~UserScript() {
 }
 
 void UserScript::add_url_pattern(const URLPattern& pattern) {
   url_patterns_.push_back(pattern);
 }
 
 void UserScript::clear_url_patterns() { url_patterns_.clear(); }
 
 bool UserScript::MatchesUrl(const GURL& url) const {
-  if (url_patterns_.size() > 0) {
+  if (!url_patterns_.empty()) {
     if (!UrlMatchesPatterns(&url_patterns_, url))
       return false;
   }
 
-  if (globs_.size() > 0) {
+  if (!globs_.empty()) {
     if (!UrlMatchesGlobs(&globs_, url))
       return false;
   }
 
-  if (exclude_globs_.size() > 0) {
+  if (!exclude_globs_.empty()) {
     if (UrlMatchesGlobs(&exclude_globs_, url))
       return false;
   }
 
   return true;
 }
 
 void UserScript::File::Pickle(::Pickle* pickle) const {
   pickle->WriteString(url_.spec());
   // Do not write path. It's not needed in the renderer.
@@ skipping 109 matching lines @@
   // Read css scripts.
   size_t num_css_files = 0;
   CHECK(pickle.ReadSize(iter, &num_css_files));
   css_scripts_.clear();
   for (size_t i = 0; i < num_css_files; ++i) {
     File file;
     file.Unpickle(pickle, iter);
     css_scripts_.push_back(file);
   }
 }