MacViews: Consolidate flags. Just use --secondary-ui-md to enable MacViews.

chrome/browser/ui/browser_dialogs.h

Index: chrome/browser/ui/browser_dialogs.h
diff --git a/chrome/browser/ui/browser_dialogs.h b/chrome/browser/ui/browser_dialogs.h
index f1185ee655436f1549a6eddc0e100e6a230ba364..10dc1ffbc0675a7bb476a8dc687fc7e149e4d5d8 100644
--- a/chrome/browser/ui/browser_dialogs.h
+++ b/chrome/browser/ui/browser_dialogs.h
@@ -25,10 +25,6 @@ class GURL;
 class LoginHandler;
 class Profile;
 
-namespace base {
-struct Feature;
-}
-
 namespace bookmarks {
 class BookmarkBubbleObserver;
 }
@@ -66,14 +62,6 @@ class WebDialogDelegate;
 
 namespace chrome {
 
-#if defined(OS_MACOSX)
-// Makes ToolkitViewsDialogsEnabled() available to chrome://flags.
-extern const base::Feature kMacViewsNativeDialogs;
-
-// Makes ToolkitViewsWebUIDialogsEnabled() available to chrome://flags.
-extern const base::Feature kMacViewsWebUIDialogs;
-#endif  // OS_MACOSX
-
 // Shows or hides the Task Manager. |browser| can be NULL when called from Ash.
 // Returns a pointer to the underlying TableModel, which can be ignored, or used
 // for testing.
@@ -122,14 +110,6 @@ content::ColorChooser* ShowColorChooser(content::WebContents* web_contents,
 
 #if defined(OS_MACOSX)
 
-// For Mac, returns true if Chrome should show an equivalent toolkit-views based
-// dialog instead of a native-looking Cocoa dialog.
-bool ToolkitViewsDialogsEnabled();
-
-// For Mac, returns true if Chrome should show an equivalent toolkit-views based
-// dialog instead of a WebUI-styled Cocoa dialog.
-bool ToolkitViewsWebUIDialogsEnabled();
-
 // Shows a Views website settings bubble at the given anchor point.
 void ShowWebsiteSettingsBubbleViewsAtPoint(
     const gfx::Point& anchor_point,