base/win: Add documentation to RegKey::Read/Write functions.

chrome/installer/util/install_util_unittest.cc

Index: chrome/installer/util/install_util_unittest.cc
diff --git a/chrome/installer/util/install_util_unittest.cc b/chrome/installer/util/install_util_unittest.cc
index 9d5341de199f0acbf767bd65e9cf4ac40883076f..1047be141fd406dc5e5ab06558339752140f7263 100644
--- a/chrome/installer/util/install_util_unittest.cc
+++ b/chrome/installer/util/install_util_unittest.cc
@@ -137,7 +137,7 @@ TEST_F(InstallUtilTest, UpdateInstallerStage) {
     DWORD value;
     EXPECT_EQ(ERROR_SUCCESS,
               RegKey(root, state_key_path.c_str(), KEY_QUERY_VALUE)
-                  .ReadValueDW(installer::kInstallerExtraCode1, &value));
+                  .ReadValue(installer::kInstallerExtraCode1, &value));
     EXPECT_EQ(static_cast<DWORD>(installer::BUILDING), value);
   }
 
@@ -153,7 +153,7 @@ TEST_F(InstallUtilTest, UpdateInstallerStage) {
     DWORD value;
     EXPECT_EQ(ERROR_SUCCESS,
               RegKey(root, state_key_path.c_str(), KEY_QUERY_VALUE)
-                  .ReadValueDW(installer::kInstallerExtraCode1, &value));
+                  .ReadValue(installer::kInstallerExtraCode1, &value));
     EXPECT_EQ(static_cast<DWORD>(installer::BUILDING), value);
   }
 
@@ -168,7 +168,7 @@ TEST_F(InstallUtilTest, UpdateInstallerStage) {
     DWORD value;
     EXPECT_EQ(ERROR_FILE_NOT_FOUND,
               RegKey(root, state_key_path.c_str(), KEY_QUERY_VALUE)
-                  .ReadValueDW(installer::kInstallerExtraCode1, &value));
+                  .ReadValue(installer::kInstallerExtraCode1, &value));
   }
 }