Fix issue where cmd-w was hard-coded to closing a browser tab regardless of t...

chrome/browser/cocoa/browser_window_controller.mm

Index: chrome/browser/cocoa/browser_window_controller.mm
===================================================================
--- chrome/browser/cocoa/browser_window_controller.mm	(revision 16871)
+++ chrome/browser/cocoa/browser_window_controller.mm	(working copy)
@@ -309,6 +309,11 @@
       // Generate return value (enabled state)
       enable = browser_->command_updater()->IsCommandEnabled(tag) ? YES : NO;
 
+      // Disable "close tab" if we're not the key window or if there's only
+      // one tab.
+      if (tag == IDC_CLOSE_TAB)
+        enable &= [self numberOfTabs] > 1 && [[self window] isKeyWindow];
+
       // If the item is toggleable, find it's toggle state and
       // try to update it.  This is a little awkward, but the alternative is
       // to check after a commandDispatch, which seems worse.