[Mac] Fix BMB chevron button being black on Chrome open.

It seems the issue is caused by the button being drawn into
a layer early on and being cached. Adding a -setNeedsDisplay:
when we actually determine whether it should be visible fixes
the problem - so that the first actual paint to the screen
has the correct appearance.

I'm not sure why Cocoa draws it to a layer earlier than this
(this doesn't happen for other buttons), nor why it's background
color is black when that happens. However, this change does fix
the bad appearance.

BUG=563395

Review URL: https://codereview.chromium.org/1630453002

Cr-Commit-Position: refs/heads/master@{#371344}

1 files changed, 5 insertions, 0 deletions

diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
index 0d5f650..fb6d1c0 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_controller.mm
@@ -865,6 +865,11 @@ void RecordAppLaunch(Profile* profile, GURL url) {
   int bookmarkChildren = bookmarkModel_->bookmark_bar_node()->child_count();
   if (bookmarkChildren > displayedButtonCount_) {
     [offTheSideButton_ setHidden:NO];
+    // Set the off the side button as needing re-display. This is needed to
+    // avoid the button being shown with a black background the first time
+    // it's displayed. See https://codereview.chromium.org/1630453002/ for
+    // more context.
+    [offTheSideButton_ setNeedsDisplay:YES];
   } else {
     // If we just deleted the last item in an off-the-side menu so the
     // button will be going away, make sure the menu goes away.