Sad Tab view for the Mac.

chrome/browser/tab_contents/web_contents_view_mac.mm

Index: chrome/browser/tab_contents/web_contents_view_mac.mm
===================================================================
--- chrome/browser/tab_contents/web_contents_view_mac.mm	(revision 9874)
+++ chrome/browser/tab_contents/web_contents_view_mac.mm	(working copy)
@@ -5,6 +5,7 @@
 #include "chrome/browser/tab_contents/web_contents_view_mac.h"
 
 #include "chrome/browser/browser.h" // TODO(beng): this dependency is awful.
+#include "chrome/browser/cocoa/sad_tab_view.h"
 #include "chrome/browser/renderer_host/render_widget_host.h"
 #include "chrome/browser/renderer_host/render_widget_host_view_mac.h"
 #include "chrome/browser/tab_contents/web_contents.h"
@@ -18,6 +19,10 @@
 
 WebContentsViewMac::WebContentsViewMac(WebContents* web_contents)
     : web_contents_(web_contents) {
+  registrar_.Add(this, NotificationType::WEB_CONTENTS_CONNECTED,
+                 Source<WebContents>(web_contents));
+  registrar_.Add(this, NotificationType::WEB_CONTENTS_DISCONNECTED,
+                 Source<WebContents>(web_contents));
 }
 
 WebContentsViewMac::~WebContentsViewMac() {
@@ -232,6 +237,34 @@
   widget_host->Init();
 }
 
+void WebContentsViewMac::Observe(NotificationType type,
+                                 const NotificationSource& source,
+                                 const NotificationDetails& details) {
+  switch (type.value) {
+    case NotificationType::WEB_CONTENTS_CONNECTED: {
+      if (sad_tab_.get()) {
+        [sad_tab_.get() removeFromSuperview];
+        sad_tab_.reset();
+      }
+      break;
+    }
+    case NotificationType::WEB_CONTENTS_DISCONNECTED: {
+      SadTabView* view = [[SadTabView alloc] initWithFrame:NSZeroRect];
+      CFRetain(view);
+      [view release];
+      sad_tab_.reset(view);
+      
+      // Set as the dominant child.
+      [cocoa_view_.get() addSubview:view];
+      [view setFrame:[cocoa_view_.get() bounds]];
+      [view setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
+      break;
+    }
+    default:
+      NOTREACHED() << "Got a notification we didn't register for.";
+  }
+}
+
 @implementation WebContentsViewCocoa
 
 // Tons of stuff goes here, where we grab events going on in Cocoaland and send