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

chrome/common/extensions/user_script.cc

Index: chrome/common/extensions/user_script.cc
diff --git a/chrome/common/extensions/user_script.cc b/chrome/common/extensions/user_script.cc
index f71de5c3a4ee816778f8b148f38ae2deb66e2459..b66dee9445f0b416b1740e7ae12d63c694ccb79e 100644
--- a/chrome/common/extensions/user_script.cc
+++ b/chrome/common/extensions/user_script.cc
@@ -79,17 +79,17 @@ void UserScript::add_url_pattern(const URLPattern& 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;
   }