Have each SandboxedProcessLauncherDelegate maintain a zygote.

chrome/browser/memory_details.cc

 // 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.
 
 #include "chrome/browser/memory_details.h"
 
 #include <algorithm>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 192 matching lines @@
 
   // Now go do expensive memory lookups on the blocking pool.
   BrowserThread::GetBlockingPool()->PostWorkerTaskWithShutdownBehavior(
       FROM_HERE,
       base::Bind(&MemoryDetails::CollectProcessData, this, mode, child_info),
       base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
 }
 
 void MemoryDetails::CollectChildInfoOnUIThread() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-#if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
-  const pid_t zygote_pid = content::ZygoteHost::GetInstance()->GetPid();
-#endif
-
   ProcessData* const chrome_browser = ChromeBrowser();
 
   // First pass, collate the widgets by process ID.
   std::map<base::ProcessId, std::vector<RenderWidgetHost*>> widgets_by_pid;
   scoped_ptr<content::RenderWidgetHostIterator> widget_it(
       RenderWidgetHost::GetRenderWidgetHosts());
   while (content::RenderWidgetHost* widget = widget_it->GetNextHost()) {
     // Ignore processes that don't have a connection, such as crashed tabs.
     if (!widget->GetProcess()->HasConnection())
       continue;
@@ skipping 131 matching lines @@
                chrome::kChromeUIMemoryURL)) ||
           (pending_entry &&
            base::LowerCaseEqualsASCII(
                pending_entry->GetVirtualURL().spec(),
                chrome::kChromeUIMemoryURL))) {
         process.is_diagnostics = true;
       }
     }
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
-    if (process.pid == zygote_pid) {
+    if (content::ZygoteHost::GetInstance()->IsZygotePid(process.pid)) {
       process.process_type = content::PROCESS_TYPE_ZYGOTE;
     }
 #endif
   }
 
   // Get rid of other Chrome processes that are from a different profile.
   auto is_unknown = [](ProcessMemoryInformation& process) {
     return process.process_type == content::PROCESS_TYPE_UNKNOWN;
   };
   auto& vector = chrome_browser->processes;
   vector.erase(std::remove_if(vector.begin(), vector.end(), is_unknown),
                vector.end());
 
   OnDetailsAvailable();
 }