mac: Add traffic lights to fullscreen mode in Yosemite.

chrome/browser/ui/cocoa/browser_window_controller_private.mm

Index: chrome/browser/ui/cocoa/browser_window_controller_private.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_controller_private.mm b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
index aff989b80de903db37432800a806beb4eef00a38..6ffb2ca5ebe248c5932e4db0a79fea4b9b7a256d 100644
--- a/chrome/browser/ui/cocoa/browser_window_controller_private.mm
+++ b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
@@ -333,9 +333,21 @@ willPositionSheet:(NSWindow*)sheet
   maxY -= tabStripHeight;
   [tabStripView setFrame:NSMakeRect(0, maxY, width, tabStripHeight)];
 
+  // In Yosemite fullscreen, manually add the fullscreen controls to the tab
+  // strip.
+  BOOL addControlsInFullscreen =
+      [self isInAppKitFullscreen] && base::mac::IsOSYosemiteOrLater();
+
   // Set left indentation based on fullscreen mode status.
-  [tabStripController_ setLeftIndentForControls:(fullscreen ? 0 :
-      [[tabStripController_ class] defaultLeftIndentForControls])];
+  CGFloat leftIndent = 0;
+  if (!fullscreen || addControlsInFullscreen)
+    leftIndent = [[tabStripController_ class] defaultLeftIndentForControls];
+  [tabStripController_ setLeftIndentForControls:leftIndent];
+
+  if (addControlsInFullscreen)
+    [tabStripController_ addWindowControls];
+  else
+    [tabStripController_ removeWindowControls];
 
   // Lay out the icognito/avatar badge because calculating the indentation on
   // the right depends on it.