base: Add SetEnv() to EnvVarGetter class and get rid of the some ifdefs.

base/xdg_util_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 "base/xdg_util.h"
 
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #include "base/env_var.h"
 
 using ::testing::_;
 using ::testing::Return;
 using ::testing::SetArgumentPointee;
 using ::testing::StrEq;
 
 namespace {
 
 class MockEnvVarGetter : public base::EnvVarGetter {
  public:
   MOCK_METHOD2(GetEnv, bool(const char*, std::string* result));
+  MOCK_METHOD2(SetEnv, void(const char*, const std::string& new_value));
 };
 
 const char* kGnome = "gnome";
 const char* kKDE4 = "kde4";
 const char* kKDE = "kde";
 const char* kXFCE = "xfce";
 
 }  // namespace
 
 TEST(XDGUtilTest, GetDesktopEnvironmentGnome) {
@@ skipping 28 matching lines @@
 
 TEST(XDGUtilTest, GetDesktopEnvironmentXFCE) {
   MockEnvVarGetter getter;
   EXPECT_CALL(getter, GetEnv(_, _)).WillRepeatedly(Return(false));
   EXPECT_CALL(getter, GetEnv(StrEq("DESKTOP_SESSION"), _))
       .WillOnce(DoAll(SetArgumentPointee<1>(kXFCE), Return(true)));
 
   EXPECT_EQ(base::DESKTOP_ENVIRONMENT_XFCE,
             base::GetDesktopEnvironment(&getter));
 }