Revert of Add PERSISTENT_MAP usage for GpuMemoryBuffers.

content/browser/browser_main_loop.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 "content/browser/browser_main_loop.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/memory_pressure_monitor.h"
@@ skipping 451 matching lines @@
     size_t process_limit;
     if (base::StringToSizeT(limit_string, &process_limit)) {
       RenderProcessHost::SetMaxRendererProcessCount(process_limit);
     }
   }
 #endif  // !defined(OS_IOS)
 
   if (parsed_command_line_.HasSwitch(switches::kEnableNativeGpuMemoryBuffers)) {
     BrowserGpuChannelHostFactory::EnableGpuMemoryBufferFactoryUsage(
         gfx::GpuMemoryBuffer::MAP);
-    BrowserGpuChannelHostFactory::EnableGpuMemoryBufferFactoryUsage(
-        gfx::GpuMemoryBuffer::PERSISTENT_MAP);
   }
 
 #if defined(USE_OZONE)
   BrowserGpuChannelHostFactory::EnableGpuMemoryBufferFactoryUsage(
       gfx::GpuMemoryBuffer::SCANOUT);
 #endif
 
   base::DiscardableMemoryAllocator::SetInstance(
       HostDiscardableSharedMemoryManager::current());
 
@@ skipping 845 matching lines @@
 
 void BrowserMainLoop::EndStartupTracing() {
   is_tracing_startup_ = false;
   TracingController::GetInstance()->DisableRecording(
       TracingController::CreateFileSink(
           startup_trace_file_,
           base::Bind(OnStoppedStartupTracing, startup_trace_file_)));
 }
 
 }  // namespace content