Cocoa: Fix a constraint violation when navigating away from a detached bookmark bar.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm

Index: chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
index a38b2a660729d81749d63ae72f435946c135349a..c0dff05c60fca998e21a2bd703e55e5c1a72f051 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
@@ -165,6 +165,9 @@ void RecordAppLaunch(Profile* profile, GURL url) {
 
 @interface BookmarkBarController ()
 
+// Updates the sizes and positions of the subviews.
+- (void)layoutSubviews;
+
 // Moves to the given next state (from the current state), possibly animating.
 // If |animate| is NO, it will stop any running animation and jump to the given
 // state. If YES, it may either (depending on implementation) jump to the end of
@@ -558,6 +561,14 @@ void RecordAppLaunch(Profile* profile, GURL url) {
   [self closeFolderAndStopTrackingMenus];
 }
 
+- (void)layoutToFrame:(NSRect)frame {
+  // The view should be pinned to the top of the window with a flexible width.
+  DCHECK_EQ(NSViewWidthSizable | NSViewMinYMargin,
+            [[self view] autoresizingMask]);
+  [[self view] setFrame:frame];
+  [self layoutSubviews];
+}
+
 // Change the layout of the bookmark bar's subviews in response to a visibility
 // change (e.g., show or hide the bar) or style change (attached or floating).
 - (void)layoutSubviews {