Add a CodeToNativeKeycode helper that converts UIEvent code to native code.

content/public/test/browser_test_utils.h

Index: content/public/test/browser_test_utils.h
diff --git a/content/public/test/browser_test_utils.h b/content/public/test/browser_test_utils.h
index 4dce33e2df01ceebc72aab4bc34a01265c7fc7fb..ea8b79c50f9d9d5a2ca409ff9e705fbf15dffa98 100644
--- a/content/public/test/browser_test_utils.h
+++ b/content/public/test/browser_test_utils.h
@@ -79,6 +79,7 @@ void SimulateMouseEvent(WebContents* web_contents,
                         const gfx::Point& point);
 
 // Sends a key press asynchronously.
+// The native code of the key event will be set to 0.

[Wez, 2013/09/05 00:16:33]

This should be "... will be set to InvalidNativeKeycode()." or similar.

[weitao, 2013/09/05 07:49:17]

Done.

 void SimulateKeyPress(WebContents* web_contents,
                       ui::KeyboardCode key,
                       bool control,
@@ -86,6 +87,18 @@ void SimulateKeyPress(WebContents* web_contents,
                       bool alt,
                       bool command);
 
+// Sends a key press asynchronously.
+// The native code of the key event will be set based on |code|.

[Wez, 2013/09/05 00:16:33]

This should refer to the DOM4 UI Events spec, e.g. "|code| specifies the DOM4 UI
Events value for the key."

nit: Rename the |key| parameter to |keyCode|, since that's what it actually sets
in DOM language, here and above.

[weitao, 2013/09/05 07:49:17]

Done.

+// TODO: should we have an overload that takes only KeyboardCode or
+// |code| and generates the other one based on US keyboard layout?

[Wez, 2013/09/05 00:16:33]

nit: This isn't really a TODO, so I don't think the comment adds anything.

[weitao, 2013/09/05 07:49:17]

Done.

+void SimulateKeyPress(WebContents* web_contents,

[Wez, 2013/09/05 00:16:33]

As per style guide, this shouldn't be an override, but e.g.
SimulateKeyPressWithCode().

[weitao, 2013/09/05 07:49:17]

Done.

+                      ui::KeyboardCode key,
+                      const char* code,
+                      bool control,
+                      bool shift,
+                      bool alt,
+                      bool command);
+
 // Allow ExecuteScript* methods to target either a WebContents or a
 // RenderViewHost.  Targetting a WebContents means executing script in the
 // RenderViewHost returned by WebContents::GetRenderViewHost(), which is the