Check that all RenderProcessHost(s) are terminated.

content/browser/browser_main_loop.cc

Index: content/browser/browser_main_loop.cc
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index 80c84a7309f63d0ee3fcdb65812144932c57a1cf..2368fbdec1e671590a1c3e95c80e566ff2787fab 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -1079,6 +1079,11 @@ void BrowserMainLoop::ShutdownThreadsAndCleanUp() {
       }
       case BrowserThread::IO: {
         TRACE_EVENT0("shutdown", "BrowserMainLoop::Subsystem:IOThread");
+        // At this point we should have removed all tabs which will lead to all
+        // RenderProcessHostImpl instances getting terminated.
+        // It is suspected that this is not happening: crbug.com/608049.
+        // TODO(alokp): Remove this after fixing the issue.
+        RenderProcessHostImpl::CheckAllTerminated();
         ResetThread_IO(std::move(io_thread_));
         break;
       }