Re-enable native UI for {frame:'chrome'} in app windows.

chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm

Index: chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm b/chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm
index 88b5c4fe3c896e524d508c0e4d53d8922565e3b1..afea8ed8979528b90ef4875d180f0d5dc249e63f 100644
--- a/chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/extensions/shell_window_cocoa.mm
@@ -79,18 +79,18 @@
 
 @end
 
-@interface ShellNSWindow : ChromeEventProcessingWindow
-
-- (void)drawCustomFrameRect:(NSRect)rect forView:(NSView*)view;
-
-@end
-
 // This is really a method on NSGrayFrame, so it should only be called on the
 // view passed into -[NSWindow drawCustomFrameRect:forView:].
 @interface NSView (PrivateMethods)
 - (CGFloat)roundedCornerRadius;
 @end
 
+@interface ShellNSWindow : ChromeEventProcessingWindow
+
+- (void)drawCustomFrameRect:(NSRect)rect forView:(NSView*)view;
+
+@end
+
 @implementation ShellNSWindow
 
 - (void)drawCustomFrameRect:(NSRect)rect forView:(NSView*)view {
@@ -109,6 +109,14 @@
   NSRectFill(rect);
 }
 
+@end
+
+@interface ShellFramelessNSWindow : ShellNSWindow
+
+@end
+
+@implementation ShellFramelessNSWindow
+
 + (NSRect)frameRectForContentRect:(NSRect)contentRect
                         styleMask:(NSUInteger)mask {
   return contentRect;
@@ -168,7 +176,15 @@ ShellWindowCocoa::ShellWindowCocoa(ShellWindow* shell_window,
   NSUInteger style_mask = NSTitledWindowMask | NSClosableWindowMask |
                           NSMiniaturizableWindowMask | NSResizableWindowMask |
                           NSTexturedBackgroundWindowMask;
-  scoped_nsobject<NSWindow> window([[ShellNSWindow alloc]
+  scoped_nsobject<NSWindow> window;
+  if (has_frame_)

[Robert Sesek, 2012/09/17 18:50:45]

Multi-line bodies need {} braces.

+    window.reset([[ShellNSWindow alloc]
+      initWithContentRect:cocoa_bounds

[Robert Sesek, 2012/09/17 18:50:45]

nit: continuations need to be indented 4 spaces from the previous line, and on
188.

+                styleMask:style_mask
+                  backing:NSBackingStoreBuffered
+                    defer:NO]);
+  else
+    window.reset([[ShellFramelessNSWindow alloc]
       initWithContentRect:cocoa_bounds
                 styleMask:style_mask
                   backing:NSBackingStoreBuffered