Reland r786979, part 3: switch ToolbarAccountIconContainer.

The original CL was landed in one piece and reverted due to apparent
perf regressions.  Reland in sections to try and determine more
precisely whether there is any perf impact.

This CL switches ToolbarAccountIconContainer away from ButtonObserver
and over to callbacks.

If this causes perf regressions, something about the actual callback
dispatch is weird.

Bug: none
Change-Id: I7c8ef2dd4cb89330c95677e3e0d88add77776dec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2347327
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Allen Bauer <kylixrd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#796627}

chrome/browser/ui/views/toolbar/toolbar_icon_container_view.cc

@@ -6,7 +6,6 @@
 
 #include <memory>
 
-#include "base/bind_helpers.h"
 #include "base/stl_util.h"
 #include "chrome/browser/themes/theme_properties.h"
 #include "chrome/browser/ui/layout_constants.h"
@@ -101,10 +100,12 @@ void ToolbarIconContainerView::ObserveButton(views::Button* button) {
   // We don't care about the main button being highlighted.
   if (button != main_button_) {
     subscriptions_.push_back(
-        button->AddHighlightedChangedCallback(base::DoNothing()));
+        button->AddHighlightedChangedCallback(base::BindRepeating(
+            &ToolbarIconContainerView::OnButtonHighlightedChanged,
+            base::Unretained(this), base::Unretained(button))));
   }
-  subscriptions_.push_back(button->AddStateChangedCallback(base::DoNothing()));
-  button->AddButtonObserver(this);
+  subscriptions_.push_back(button->AddStateChangedCallback(base::BindRepeating(
+      &ToolbarIconContainerView::UpdateHighlight, base::Unretained(this))));
   button->AddObserver(this);
 }
 
@@ -132,22 +133,6 @@ bool ToolbarIconContainerView::IsHighlighted() {
   return ShouldDisplayHighlight();
 }
 
-void ToolbarIconContainerView::OnHighlightChanged(
-    views::Button* observed_button,
-    bool highlighted) {
-  // We don't care about the main button being highlighted.
-  if (observed_button == main_button_)
-    return;
-
-  OnButtonHighlightedChanged(observed_button);
-}
-
-void ToolbarIconContainerView::OnStateChanged(
-    views::Button* observed_button,
-    views::Button::ButtonState old_state) {
-  UpdateHighlight();
-}
-
 void ToolbarIconContainerView::OnViewFocused(views::View* observed_view) {
   UpdateHighlight();
 }

chrome/browser/ui/views/toolbar/toolbar_icon_container_view.h

@@ -10,7 +10,6 @@
 #include "base/observer_list.h"
 #include "ui/gfx/animation/animation_delegate.h"
 #include "ui/views/controls/button/button.h"
-#include "ui/views/controls/button/button_observer.h"
 #include "ui/views/layout/animating_layout_manager.h"
 #include "ui/views/layout/flex_layout.h"
 #include "ui/views/view.h"
@@ -18,7 +17,6 @@
 // A general view container for any type of toolbar icons.
 class ToolbarIconContainerView : public views::View,
                                  public gfx::AnimationDelegate,
-                                 public views::ButtonObserver,
                                  public views::ViewObserver {
  public:
   class Observer : public base::CheckedObserver {
@@ -49,12 +47,6 @@ class ToolbarIconContainerView : public views::View,
 
   bool IsHighlighted();
 
-  // views::ButtonObserver:
-  void OnHighlightChanged(views::Button* observed_button,
-                          bool highlighted) override;
-  void OnStateChanged(views::Button* observed_button,
-                      views::Button::ButtonState old_state) override;
-
   // views::ViewObserver:
   void OnViewFocused(views::View* observed_view) override;
   void OnViewBlurred(views::View* observed_view) override;