[ios clean] Use dispatcher for showing TabStrip

ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm

Index: ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm
diff --git a/ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm b/ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm
index 0f76625e3eb894306e4d1533ce0f511bb1a00b19..1854300e779f2eed51e57f46ea52441ed9aa1e46 100644
--- a/ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm
+++ b/ios/clean/chrome/browser/ui/tab_strip/tab_strip_toolbar.mm
@@ -49,6 +49,7 @@ CGFloat kSpacing = 10.0f;
   UIButton* button = [UIButton buttonWithType:UIButtonTypeSystem];
   [button setImage:[ChromeIcon closeIcon] forState:UIControlStateNormal];
   [button setTintColor:[UIColor whiteColor]];
+  // TODO(crbug.com/733453): Use dispatcher instead of responder chain.

[sczs, 2017/06/15 01:15:44]

Adding this TODO so Ed doesn't miss it. I know he was planning on refactoring
this at some point, so I didn't think adding all the plumbing was worth it right
now.

   [button addTarget:nil
                 action:@selector(hideTabStrip:)
       forControlEvents:UIControlEventTouchUpInside];