Mac: Don't replace the alpha on the detached toolbar separator color.

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

Index: chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm
diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm
index 56cc537141dfb3b092dc8b315ca850443588f82e..fe88ea1681a5d75164726950d66ee8a9650bb4b8 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm
@@ -86,7 +86,6 @@
         tp.GetNSColor(ThemeProperties::COLOR_DETACHED_BOOKMARK_BAR_SEPARATOR);
     strokeColor = [[self strokeColor] blendedColorWithFraction:morph
                                                        ofColor:strokeColor];
-    strokeColor = [strokeColor colorWithAlphaComponent:0.5];
     [strokeColor set];
     NSRectFillUsingOperation(NSIntersectionRect(strokeRect, dirtyRect),
                              NSCompositeSourceOver);