Revert of content: Enable native GpuMemoryBuffers by default on MacOSX.

content/browser/gpu/browser_gpu_memory_buffer_manager.cc

 // Copyright 2014 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/gpu/browser_gpu_memory_buffer_manager.h"
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/strings/stringprintf.h"
@@ skipping 69 matching lines @@
   GpuMemoryBufferFactory::GetSupportedTypes(&supported_types);
   DCHECK(!supported_types.empty());
 
   // The GPU service will always use the preferred type.
   return supported_types[0];
 }
 
 std::vector<GpuMemoryBufferFactory::Configuration>
 GetSupportedGpuMemoryBufferConfigurations(gfx::GpuMemoryBufferType type) {
   std::vector<GpuMemoryBufferFactory::Configuration> configurations;
-#if defined(OS_MACOSX)
-  bool enable_native_gpu_memory_buffers =
-      !base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kDisableNativeGpuMemoryBuffers);
-#else
-  bool enable_native_gpu_memory_buffers =
-      base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableNativeGpuMemoryBuffers);
-#endif
-  if (enable_native_gpu_memory_buffers) {
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableNativeGpuMemoryBuffers)) {
     const GpuMemoryBufferFactory::Configuration kNativeConfigurations[] = {
         {gfx::GpuMemoryBuffer::R_8, gfx::GpuMemoryBuffer::MAP},
         {gfx::GpuMemoryBuffer::R_8, gfx::GpuMemoryBuffer::PERSISTENT_MAP},
         {gfx::GpuMemoryBuffer::RGBA_4444, gfx::GpuMemoryBuffer::MAP},
         {gfx::GpuMemoryBuffer::RGBA_4444, gfx::GpuMemoryBuffer::PERSISTENT_MAP},
         {gfx::GpuMemoryBuffer::RGBA_8888, gfx::GpuMemoryBuffer::MAP},
         {gfx::GpuMemoryBuffer::RGBA_8888, gfx::GpuMemoryBuffer::PERSISTENT_MAP},
         {gfx::GpuMemoryBuffer::BGRA_8888, gfx::GpuMemoryBuffer::MAP},
         {gfx::GpuMemoryBuffer::BGRA_8888,
          gfx::GpuMemoryBuffer::PERSISTENT_MAP}};
@@ skipping 458 matching lines @@
   }
 
   GpuProcessHost* host = GpuProcessHost::FromID(buffer_it->second.gpu_host_id);
   if (host)
     host->DestroyGpuMemoryBuffer(id, client_id, sync_point);
 
   buffers.erase(buffer_it);
 }
 
 }  // namespace content