[ios] Adds a CommandDispatcher to Browser.

ios/shared/chrome/browser/ui/browser_list/browser.mm

Index: ios/shared/chrome/browser/ui/browser_list/browser.mm
diff --git a/ios/shared/chrome/browser/ui/browser_list/browser.mm b/ios/shared/chrome/browser/ui/browser_list/browser.mm
index 6b84e93127167dd34396da4f5b42b7b53ef6d600..5fc2496d2b5dc905c562a30ed59eb3be1359aca4 100644
--- a/ios/shared/chrome/browser/ui/browser_list/browser.mm
+++ b/ios/shared/chrome/browser/ui/browser_list/browser.mm
@@ -8,13 +8,15 @@
 #include "base/memory/ptr_util.h"
 #import "ios/shared/chrome/browser/tabs/web_state_list.h"
 #import "ios/shared/chrome/browser/ui/browser_list/browser_web_state_list_delegate.h"
+#import "ios/shared/chrome/browser/ui/commands/command_dispatcher.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 Browser::Browser(ios::ChromeBrowserState* browser_state)
-    : browser_state_(browser_state) {
+    : dispatcher_([[CommandDispatcher alloc] init]),
+      browser_state_(browser_state) {
   DCHECK(browser_state_);
   web_state_list_delegate_ =
       base::MakeUnique<BrowserWebStateListDelegate>(this);