MemoryCoordinator checks if ServiceWorker exists on the suspending process

content/public/browser/render_process_host.h

Index: content/public/browser/render_process_host.h
diff --git a/content/public/browser/render_process_host.h b/content/public/browser/render_process_host.h
index 8edeb8458a3428f17d5d3b0b7348886335a15989..bc0de81fc23cad1e9beccaac01f192781ce699b6 100644
--- a/content/public/browser/render_process_host.h
+++ b/content/public/browser/render_process_host.h
@@ -304,10 +304,29 @@ class CONTENT_EXPORT RenderProcessHost : public IPC::Sender,
   // Returns true if this process currently has backgrounded priority.
   virtual bool IsProcessBackgrounded() const = 0;
 
-  // Called when the existence of the other renderer process which is connected
-  // to the Worker in this renderer process has changed.
+  // Returns the total number of shared worker and service workers.

[falken, 2016/12/14 08:21:15]

nit: This isn't really the total number of workers, it's the ref count which in
SharedWorker case is quite different (indeed some of us got confused about
that). I guess "the sum of the shared worker and service worker ref counts"

[shimazu, 2016/12/14 09:34:04]

Thanks, updated.

+  virtual size_t GetWorkerRefCount() const = 0;
+
+  // Counts the number of service workers who live on this process. The service
+  // worker ref count is incremented when the worker is trying to look for or
+  // allocate a process, and decremented when worker's shutdown sequence is
+  // completed.
   virtual void IncrementServiceWorkerRefCount() = 0;
   virtual void DecrementServiceWorkerRefCount() = 0;
+
+  // Called when the existence of the other renderer process which is connected
+  // to the Worker in this renderer process has changed.
+
+  // The shared worker ref count is nonzero if any other process is connected to
+  // a shared worker in this process, or a new shared worker is being created in
+  // this process. IncrementSharedWorkerRefCount is called in two cases:
+  // - there was no external renderer connected to a shared worker in this
+  //   process, and now there is at least one
+  // - a new worker is being created in this process.
+  // DecrementSharedWorkerRefCount is called in two cases:
+  // - there was an external renderer connected to a shared worker in this
+  //    process, and now there is none
+  // - a new worker finished being created in this process
   virtual void IncrementSharedWorkerRefCount() = 0;
   virtual void DecrementSharedWorkerRefCount() = 0;