ResourceScheduler get visual signal from RenderViewHostImpl

content/browser/loader/resource_scheduler.cc

Index: content/browser/loader/resource_scheduler.cc
diff --git a/content/browser/loader/resource_scheduler.cc b/content/browser/loader/resource_scheduler.cc
index 85adbdb30e275631b53af88286e75b658e73a16c..9fdc35ffc8e98ed0a7c7d35c71762c72ef0e7759 100644
--- a/content/browser/loader/resource_scheduler.cc
+++ b/content/browser/loader/resource_scheduler.cc
@@ -12,6 +12,7 @@
 #include "content/public/browser/resource_controller.h"
 #include "content/public/browser/resource_request_info.h"
 #include "content/public/browser/resource_throttle.h"
+#include "content/public/browser/web_contents_observer.h"
 #include "ipc/ipc_message_macros.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/load_flags.h"
@@ -228,9 +229,9 @@ void ResourceScheduler::RequestQueue::Insert(
 }
 
 // Each client represents a tab.
-class ResourceScheduler::Client {
+class ResourceScheduler::Client : public content::WebContentsObserver {
  public:
-  explicit Client(ResourceScheduler* scheduler)
+  explicit Client(ResourceScheduler* scheduler, WebContentsImpl* web_contents)
       : is_audible_(false),
         is_visible_(false),

[aiolos (Not reviewing), 2014/08/15 01:45:38]

is_visible_ should just be set once here.

[Zhen Wang, 2014/08/15 18:43:01]

Done.

         is_loaded_(false),
@@ -240,9 +241,11 @@ class ResourceScheduler::Client {
         total_delayable_count_(0),
         throttle_state_(ResourceScheduler::THROTTLED) {
     scheduler_ = scheduler;
+    Observe(web_contents);
+    is_visible_ = !web_contents->IsHidden();
   }
 
-  ~Client() {
+  virtual ~Client() {
     // Update to default state and pause to ensure the scheduler has a
     // correct count of relevant types of clients.
     is_visible_ = false;
@@ -251,6 +254,16 @@ class ResourceScheduler::Client {
     UpdateThrottleState();
   }
 
+  // WebContentsObserver implementation.
+  virtual void WasShown() OVERRIDE {
+    OnVisibilityChanged(true);
+  }
+
+  // WebContentsObserver implementation.
+  virtual void WasHidden() OVERRIDE {
+    OnVisibilityChanged(false);
+  }
+
   void ScheduleRequest(
       net::URLRequest* url_request,
       ScheduledResourceRequest* request) {
@@ -288,6 +301,8 @@ class ResourceScheduler::Client {
 
   bool is_loaded() const { return is_loaded_; }
 
+  bool IsVisible() const { return is_visible_; }
+
   void OnAudibilityChanged(bool is_audible) {
     if (is_audible == is_audible_) {
       return;
@@ -731,12 +746,14 @@ void ResourceScheduler::RemoveRequest(ScheduledResourceRequest* request) {
   client->RemoveRequest(request);
 }
 
-void ResourceScheduler::OnClientCreated(int child_id, int route_id) {
+void ResourceScheduler::OnClientCreated(int child_id,
+                                        int route_id,
+                                        WebContentsImpl* web_contents) {
   DCHECK(CalledOnValidThread());
   ClientId client_id = MakeClientId(child_id, route_id);
   DCHECK(!ContainsKey(client_map_, client_id));
 
-  Client* client = new Client(this);
+  Client* client = new Client(this, web_contents);
   client_map_[client_id] = client;
 
   // TODO(aiolos): set Client visibility/audibility when signals are added
@@ -817,14 +834,6 @@ void ResourceScheduler::OnAudibilityChanged(int child_id,
   client->OnAudibilityChanged(is_audible);
 }
 
-void ResourceScheduler::OnVisibilityChanged(int child_id,
-                                            int route_id,
-                                            bool is_visible) {
-  Client* client = GetClient(child_id, route_id);
-  DCHECK(client);
-  client->OnVisibilityChanged(is_visible);
-}
-
 void ResourceScheduler::OnLoadingStateChanged(int child_id,
                                               int route_id,
                                               bool is_loaded) {
@@ -833,6 +842,12 @@ void ResourceScheduler::OnLoadingStateChanged(int child_id,
   client->OnLoadingStateChanged(is_loaded);
 }
 
+bool ResourceScheduler::IsClientVisible(int child_id, int route_id) {
+  Client* client = GetClient(child_id, route_id);
+  DCHECK(client);
+  return client->IsVisible();
+}
+
 ResourceScheduler::Client* ResourceScheduler::GetClient(int child_id,
                                                         int route_id) {
   ClientId client_id = MakeClientId(child_id, route_id);