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

chrome/installer/util/app_command.cc

Index: chrome/installer/util/app_command.cc
diff --git a/chrome/installer/util/app_command.cc b/chrome/installer/util/app_command.cc
index 588fe86fda307d9615af880aee0c6813d1e3aa1f..8454b9646234438a021bd464d026d0744fd41374 100644
--- a/chrome/installer/util/app_command.cc
+++ b/chrome/installer/util/app_command.cc
@@ -42,14 +42,14 @@ bool AppCommand::Initialize(const base::win::RegKey& key) {
     return false;
   }
 
-  result = key.ReadValueDW(google_update::kRegSendsPingsField, &sends_pings);
+  result = key.ReadValue(google_update::kRegSendsPingsField, &sends_pings);
   if (result != ERROR_SUCCESS) {
     LOG(WARNING) << "Error reading " << google_update::kRegSendsPingsField
                  << " value from registry: " << result;
     return false;
   }
 
-  result = key.ReadValueDW(google_update::kRegWebAccessibleField, &is_web_acc);
+  result = key.ReadValue(google_update::kRegWebAccessibleField, &is_web_acc);
   if (result != ERROR_SUCCESS) {
     LOG(WARNING) << "Error reading " << google_update::kRegWebAccessibleField
                  << " value from registry: " << result;