base: Stop passing a non-const ref to ObserverListBase::Iterator.

cc/animation/layer_animation_controller.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/animation/layer_animation_controller.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "cc/animation/animation.h"
@@ skipping 937 matching lines @@
       registrar_->DidDeactivateAnimationController(this);
   }
 }
 
 void LayerAnimationController::NotifyObserversOpacityAnimated(
     float opacity,
     bool notify_active_observers,
     bool notify_pending_observers) {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     LayerAnimationValueObserver* obs;
     while ((obs = it.GetNext()) != nullptr) {
       if ((notify_active_observers && notify_pending_observers) ||
           (notify_active_observers && obs->IsActive()) ||
           (notify_pending_observers && !obs->IsActive()))
         obs->OnOpacityAnimated(opacity);
     }
   }
 }
 
 void LayerAnimationController::NotifyObserversTransformAnimated(
     const gfx::Transform& transform,
     bool notify_active_observers,
     bool notify_pending_observers) {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     LayerAnimationValueObserver* obs;
     while ((obs = it.GetNext()) != nullptr) {
       if ((notify_active_observers && notify_pending_observers) ||
           (notify_active_observers && obs->IsActive()) ||
           (notify_pending_observers && !obs->IsActive()))
         obs->OnTransformAnimated(transform);
     }
   }
 }
 
 void LayerAnimationController::NotifyObserversFilterAnimated(
     const FilterOperations& filters,
     bool notify_active_observers,
     bool notify_pending_observers) {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     LayerAnimationValueObserver* obs;
     while ((obs = it.GetNext()) != nullptr) {
       if ((notify_active_observers && notify_pending_observers) ||
           (notify_active_observers && obs->IsActive()) ||
           (notify_pending_observers && !obs->IsActive()))
         obs->OnFilterAnimated(filters);
     }
   }
 }
 
 void LayerAnimationController::NotifyObserversScrollOffsetAnimated(
     const gfx::ScrollOffset& scroll_offset,
     bool notify_active_observers,
     bool notify_pending_observers) {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     LayerAnimationValueObserver* obs;
     while ((obs = it.GetNext()) != nullptr) {
       if ((notify_active_observers && notify_pending_observers) ||
           (notify_active_observers && obs->IsActive()) ||
           (notify_pending_observers && !obs->IsActive()))
         obs->OnScrollOffsetAnimated(scroll_offset);
     }
   }
 }
 
 void LayerAnimationController::NotifyObserversAnimationWaitingForDeletion() {
   FOR_EACH_OBSERVER(LayerAnimationValueObserver,
                     value_observers_,
                     OnAnimationWaitingForDeletion());
 }
 
 bool LayerAnimationController::HasValueObserver() {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     return it.GetNext() != nullptr;
   }
   return false;
 }
 
 bool LayerAnimationController::HasActiveValueObserver() {
   if (value_observers_.might_have_observers()) {
     ObserverListBase<LayerAnimationValueObserver>::Iterator it(
-        value_observers_);
+        &value_observers_);
     LayerAnimationValueObserver* obs;
     while ((obs = it.GetNext()) != nullptr)
       if (obs->IsActive())
         return true;
   }
   return false;
 }
 
 }  // namespace cc