base/win: small improvement to RegKey API.

base/win/registry.h

Index: base/win/registry.h
diff --git a/base/win/registry.h b/base/win/registry.h
index 078e6e07d52b6bc87b200aee3d16538f95da01aa..e567bf2f0ddaa763eae032e4aa6bf64332482cec 100644
--- a/base/win/registry.h
+++ b/base/win/registry.h
@@ -33,20 +33,26 @@ class BASE_EXPORT RegKey {
   LONG CreateWithDisposition(HKEY rootkey, const wchar_t* subkey,
                              DWORD* disposition, REGSAM access);
 
-  LONG Open(HKEY rootkey, const wchar_t* subkey, REGSAM access);
-
   // Creates a subkey or open it if it already exists.
   LONG CreateKey(const wchar_t* name, REGSAM access);
 
-  // Opens a subkey
-  LONG OpenKey(const wchar_t* name, REGSAM access);
+  // Opens an existing reg key.
+  LONG Open(HKEY rootkey, const wchar_t* subkey, REGSAM access);
+
+  // Opens an existing reg key, given the full key name.

[grt (UTC plus 2), 2011/10/18 15:00:00]

full_key_name and this comment are misleading.  This method opens up a subkey of
|this| object's currently open key.  relative_key_name or subkey would both be
more appropriate, since the name is relative to the currently open key.

[tfarina, 2011/10/18 15:47:04]

Done.

+  LONG OpenKey(const wchar_t* full_key_name, REGSAM access);
 
+  // Closes this reg key.
   void Close();
 
-  DWORD ValueCount() const;
+  // Returns true if this key has the specified value.
+  bool HasValue(const wchar_t* value_name) const;

[grt (UTC plus 2), 2011/10/18 15:00:00]

The following is more accurate:
// Returns false if this key does not have the specified value, or if an error
occurs while attempting to access it.

[tfarina, 2011/10/18 15:47:04]

Done.

+
+  // Returns the number of values for this key.

[grt (UTC plus 2), 2011/10/18 15:00:00]

// Returns the number of values for this key, or 0 if the number cannot be
determined.

[tfarina, 2011/10/18 15:47:04]

Done.

+  DWORD GetValueCount() const;
 
   // Determine the nth value's name.
-  LONG ReadName(int index, std::wstring* name) const;
+  LONG GetValueNameAt(int index, std::wstring* name) const;
 
   // True while the key is valid.
   bool Valid() const { return key_ != NULL; }
@@ -58,8 +64,6 @@ class BASE_EXPORT RegKey {
   // Deletes a single value within the key.
   LONG DeleteValue(const wchar_t* name);
 
-  bool ValueExists(const wchar_t* name) const;
-
   LONG ReadValue(const wchar_t* name, void* data, DWORD* dsize,
                  DWORD* dtype) const;
   LONG ReadValue(const wchar_t* name, std::wstring* value) const;