Remove DISALLOW_COPY_AND_ASSIGN from chrome/browser/a*.

A little other miscellaneous cleanup, no functional changes.

Bug: 1010217
Change-Id: I9d1c56723c0de2293c06c810fa7175cbf5031f89
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2393633
Reviewed-by: Ted Choc <[email protected]>
Commit-Queue: David Bienvenu <[email protected]>
Cr-Commit-Position: refs/heads/master@{#806401}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index dd43b91..bcda2d5 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -6414,6 +6414,8 @@
   FlagsStateSingleton()
       : flags_state_(
             std::make_unique<flags_ui::FlagsState>(kFeatureEntries, this)) {}
+  FlagsStateSingleton(const FlagsStateSingleton&) = delete;
+  FlagsStateSingleton& operator=(const FlagsStateSingleton&) = delete;
   ~FlagsStateSingleton() override = default;
 
   static FlagsStateSingleton* GetInstance() {
@@ -6436,8 +6438,6 @@
   }
 
   std::unique_ptr<flags_ui::FlagsState> flags_state_;
-
-  DISALLOW_COPY_AND_ASSIGN(FlagsStateSingleton);
 };
 
 bool ShouldSkipNonDeprecatedFeatureEntry(const FeatureEntry& entry) {