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

base/command_line_unittest.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 <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/file_path.h"
@@ skipping 91 matching lines @@
 }
 
 // Tests behavior with an empty input string.
 TEST(CommandLineTest, EmptyString) {
 #if defined(OS_WIN)
   CommandLine cl = CommandLine::FromString(L"");
   EXPECT_TRUE(cl.command_line_string().empty());
   EXPECT_TRUE(cl.GetProgram().empty());
 #elif defined(OS_POSIX)
   CommandLine cl(0, NULL);
-  EXPECT_EQ(0U, cl.argv().size());
+  EXPECT_TRUE(cl.argv().empty());
 #endif
-  EXPECT_EQ(0U, cl.args().size());
+  EXPECT_TRUE(cl.args().empty());
 }
 
 // Test methods for appending switches to a command line.
 TEST(CommandLineTest, AppendSwitches) {
   std::string switch1 = "switch1";
   std::string switch2 = "switch2";
   std::string value = "value";
   std::string switch3 = "switch3";
   std::string value3 = "a value with spaces";
   std::string switch4 = "switch4";
@@ skipping 66 matching lines @@
   EXPECT_EQ(kProgram.value(), cl.GetProgram().value());
 
   // Verify that in the command line string, the program part is always quoted.
   CommandLine::StringType cmd(cl.command_line_string());
   CommandLine::StringType program(cl.GetProgram().value());
   EXPECT_EQ('"', cmd[0]);
   EXPECT_EQ(program, cmd.substr(1, program.length()));
   EXPECT_EQ('"', cmd[program.length() + 1]);
 }
 #endif