Revert "Create and pass shared-histogram-allocator from browser to renderer."

content/public/test/mock_render_process_host.cc

Index: content/public/test/mock_render_process_host.cc
diff --git a/content/public/test/mock_render_process_host.cc b/content/public/test/mock_render_process_host.cc
index debecdcee32b4015401e5b5e4fba4911bfae42a1..5037893190a68f8ff118e95ee72b7e58a5e7935f 100644
--- a/content/public/test/mock_render_process_host.cc
+++ b/content/public/test/mock_render_process_host.cc
@@ -263,11 +263,6 @@ ServiceRegistry* MockRenderProcessHost::GetServiceRegistry() {
   return service_registry_.get();
 }
 
-scoped_ptr<base::SharedPersistentMemoryAllocator>
-MockRenderProcessHost::TakeMetricsAllocator() {
-  return nullptr;
-}
-
 const base::TimeTicks& MockRenderProcessHost::GetInitTimeForNavigationMetrics()
     const {
   static base::TimeTicks dummy_time = base::TimeTicks::Now();