Implement basic theming for panel titlebars.

chrome/browser/ui/panels/panel_window_controller_cocoa.h

Index: chrome/browser/ui/panels/panel_window_controller_cocoa.h
diff --git a/chrome/browser/ui/panels/panel_window_controller_cocoa.h b/chrome/browser/ui/panels/panel_window_controller_cocoa.h
index 94df28d5650656d07b6fd555cb0caa9f7531de90..6445b304d2752eb3a43bdf382f83dd0cde500cf9 100644
--- a/chrome/browser/ui/panels/panel_window_controller_cocoa.h
+++ b/chrome/browser/ui/panels/panel_window_controller_cocoa.h
@@ -14,6 +14,10 @@
 #import "base/mac/cocoa_protocols.h"
 #include "base/memory/scoped_ptr.h"
 
+namespace ui {
+class ThemeProvider;
+};
+
 @class FindBarCocoaController;
 class PanelBrowserWindowCocoa;
 @class PanelTitlebarViewCocoa;
@@ -27,6 +31,8 @@ class PanelBrowserWindowCocoa;
 // Load the browser window nib and do any Cocoa-specific initialization.
 - (id)initWithBrowserWindow:(PanelBrowserWindowCocoa*)window;
 
+- (ui::ThemeProvider*)themeProvider;

[Dmitry Titov, 2011/08/25 00:08:21]

ThemedBrowserWindow looks for 3 selectors on the controller, why implement only
one? It seems at least themePatternPhase is already used in this patch. I think
themedWindowStyle will also be needed.

[dcheng, 2011/08/25 18:48:54]

We probably need all 3 eventually, but as I mentioned, I'm starting with just
the basics.

[Dmitry Titov, 2011/08/25 19:24:51]

Since you are adding plumbing in this patch, I think we should add all 3 (and a
unittest to test that they return some non-null values etc).
For example, you already use phase info in the drawing code but plumbing for it
is not complete. I agree to get more advanced painting in later patches but lets
get plumbing for themeProvider and its friends here and a test for it added to
panel_browser_window_cocoa_unittest.cc

[dcheng, 2011/08/26 23:04:42]

I've implemented the other two methods. There's some duplication in
themePatternPhase which I'm not sure how to resolve, and themedWindowStyle is
completely unused at the moment (BackgroundGradientView doesn't use it). What's
our story for incognito panels? Is it possible to have one?

+
 // Returns the TabContents' native view. It renders the content of the web page
 // in the Panel.
 - (NSView*)tabContentsView;