[subresource_filter] Add observer interface for page activation

components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc

Index: components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc
diff --git a/components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc b/components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc
index 6b57efe16887a80688b7642f60bcaca6b9c30edf..1ad008c981863cd84ca2fcea8eaf614b23d1388c 100644
--- a/components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc
+++ b/components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.cc
@@ -4,6 +4,8 @@
 
 #include "components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.h"
 
+#include <utility>
+
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
@@ -11,6 +13,7 @@
 #include "components/subresource_filter/content/browser/async_document_subresource_filter.h"
 #include "components/subresource_filter/content/browser/page_load_statistics.h"
 #include "components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.h"
+#include "components/subresource_filter/content/browser/subresource_filter_observer_manager.h"
 #include "components/subresource_filter/content/common/subresource_filter_messages.h"
 #include "content/public/browser/navigation_handle.h"
 #include "content/public/browser/navigation_throttle.h"
@@ -26,23 +29,22 @@ ContentSubresourceFilterThrottleManager::
         VerifiedRulesetDealer::Handle* dealer_handle,
         content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
+      scoped_observer_(this),
       dealer_handle_(dealer_handle),
       delegate_(delegate),
-      weak_ptr_factory_(this) {}
+      weak_ptr_factory_(this) {
+  SubresourceFilterObserverManager::CreateForWebContents(web_contents);
+  scoped_observer_.Add(
+      SubresourceFilterObserverManager::FromWebContents(web_contents));
+}
 
 ContentSubresourceFilterThrottleManager::
     ~ContentSubresourceFilterThrottleManager() {}
 
-void ContentSubresourceFilterThrottleManager::NotifyPageActivationComputed(
-    content::NavigationHandle* navigation_handle,
-    const ActivationState& activation_state) {
-  DCHECK(navigation_handle->IsInMainFrame());
-  DCHECK(!navigation_handle->HasCommitted());
-  auto it = ongoing_activation_throttles_.find(navigation_handle);
-  if (it != ongoing_activation_throttles_.end()) {
-    it->second->NotifyPageActivationWithRuleset(EnsureRulesetHandle(),
-                                                activation_state);
-  }
+void ContentSubresourceFilterThrottleManager::OnSubresourceFilterGoingAway() {
+  // Stop observing here because the observer manager could be destroyed by the
+  // time this class is destroyed.
+  scoped_observer_.RemoveAll();
 }
 
 void ContentSubresourceFilterThrottleManager::RenderFrameDeleted(
@@ -139,6 +141,26 @@ bool ContentSubresourceFilterThrottleManager::OnMessageReceived(
   return handled;
 }
 
+// Sets the desired page-level |activation_state| for the currently ongoing
+// page load, identified by its main-frame |navigation_handle|. If this method
+// is not called for a main-frame navigation, the default behavior is no
+// activation for that page load.
+void ContentSubresourceFilterThrottleManager::OnPageActivationComputed(
+    content::NavigationHandle* navigation_handle,
+    ActivationDecision activation_decision,
+    const ActivationState& activation_state) {
+  DCHECK(navigation_handle->IsInMainFrame());
+  DCHECK(!navigation_handle->HasCommitted());
+  // Do not notify the throttle if activation is disabled.
+  if (activation_state.activation_level == ActivationLevel::DISABLED)
+    return;
+  auto it = ongoing_activation_throttles_.find(navigation_handle);
+  if (it != ongoing_activation_throttles_.end()) {
+    it->second->NotifyPageActivationWithRuleset(EnsureRulesetHandle(),
+                                                activation_state);
+  }
+}
+
 void ContentSubresourceFilterThrottleManager::MaybeAppendNavigationThrottles(
     content::NavigationHandle* navigation_handle,
     std::vector<std::unique_ptr<content::NavigationThrottle>>* throttles) {