Mac: Make it easier for views to correctly draw with a theme.

chrome/browser/ui/cocoa/themed_window.h

Index: chrome/browser/ui/cocoa/themed_window.h
diff --git a/chrome/browser/ui/cocoa/themed_window.h b/chrome/browser/ui/cocoa/themed_window.h
index 592e56722ae9d984e2bcc39d2e5553bbba4afd98..ab4b18c6375a12da0716370bbb6fd19cd4c5bc9c 100644
--- a/chrome/browser/ui/cocoa/themed_window.h
+++ b/chrome/browser/ui/cocoa/themed_window.h
@@ -32,7 +32,6 @@ enum ThemeImageAlignment {
 };
 
 // Implemented by windows that support theming.
-
 @interface NSWindow (ThemeProvider)
 - (ThemeProvider*)themeProvider;
 - (ThemedWindowStyle)themedWindowStyle;
@@ -45,4 +44,17 @@ enum ThemeImageAlignment {
 - (NSPoint)themeImagePositionForAlignment:(ThemeImageAlignment)alignment;
 @end
 
+// Adopted by views that want to redraw when the theme changed, or when the
+// window's active status changed.
+@protocol ThemedWindowDrawing
+
+// Called by the window controller when the theme changed.
+- (void)windowDidChangeTheme;
+
+// Called by the window controller when the window gained or lost main window
+// status.
+- (void)windowDidChangeActive;
+
+@end
+
 #endif  // CHROME_BROWSER_UI_COCOA_THEMED_WINDOW_H_