Fix process reuse for dedicated processes when over process limit.

content/public/browser/render_process_host.h

 // Copyright (c) 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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 346 matching lines @@
 
   // Acquires the interface to the Global Resource Coordinator for this process.
   virtual resource_coordinator::ResourceCoordinatorInterface*
   GetProcessResourceCoordinator() = 0;
 
   // Whether this process is locked out from ever being reused for sites other
   // than the ones it currently has.
   virtual void SetIsNeverSuitableForReuse() = 0;
   virtual bool MayReuseHost() = 0;
 
+  // Indicates whether this RenderProcessHost is "unused".  This starts out as
+  // true for new processes and becomes false after one of the following:
+  // (1) This process commits any page.
+  // (2) This process is given to a SiteInstance that already has a site
+  //     assigned.
+  // Note that a process hosting ServiceWorkers will be implicitly handled by
+  // (2) during ServiceWorker initialization, and SharedWorkers will be handled
+  // by (1) since a page needs to commit before it can create a SharedWorker.
+  //
+  // While a process is unused, it is still suitable to host a URL that
+  // requires a dedicated process.
+  virtual bool IsUnused() = 0;
+  virtual void SetIsUsed() = 0;
+
   // Returns the current number of active views in this process.  Excludes
   // any RenderViewHosts that are swapped out.
   size_t GetActiveViewCount();
 
   // Posts |task|, if this RenderProcessHost is ready or when it becomes ready
   // (see RenderProcessHost::IsReady method).  The |task| might not run at all
   // (e.g. if |render_process_host| is destroyed before becoming ready).  This
   // function can only be called on the browser's UI thread (and the |task| will
   // be posted back on the UI thread).
   void PostTaskWhenProcessIsReady(base::OnceClosure task);
@@ skipping 49 matching lines @@
   static void SetMaxRendererProcessCount(size_t count);
 
   // Returns the current maximum number of renderer process hosts kept by the
   // content module.
   static size_t GetMaxRendererProcessCount();
 };
 
 }  // namespace content.
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_PROCESS_HOST_H_