Use OS_LINUX instead of USE_OZONE in ui/gfx/ when possible

ui/gfx/gpu_memory_buffer.h

 // Copyright 2013 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.
 
 #ifndef UI_GFX_GPU_MEMORY_BUFFER_H_
 #define UI_GFX_GPU_MEMORY_BUFFER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/memory/shared_memory.h"
 #include "build/build_config.h"
 #include "ui/gfx/buffer_types.h"
 #include "ui/gfx/generic_shared_memory_id.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/gfx_export.h"
 
-#if defined(USE_OZONE)
+#if defined(OS_LINUX)
 #include "ui/gfx/native_pixmap_handle.h"
 #elif defined(OS_MACOSX) && !defined(OS_IOS)
 #include "ui/gfx/mac/io_surface.h"
 #endif
 
 extern "C" typedef struct _ClientBuffer* ClientBuffer;
 
 namespace gfx {
 
 class ColorSpace;
@@ skipping 11 matching lines @@
 struct GFX_EXPORT GpuMemoryBufferHandle {
   GpuMemoryBufferHandle();
   GpuMemoryBufferHandle(const GpuMemoryBufferHandle& other);
   ~GpuMemoryBufferHandle();
   bool is_null() const { return type == EMPTY_BUFFER; }
   GpuMemoryBufferType type;
   GpuMemoryBufferId id;
   base::SharedMemoryHandle handle;
   uint32_t offset;
   int32_t stride;
-#if defined(USE_OZONE)
+#if defined(OS_LINUX)
   NativePixmapHandle native_pixmap_handle;
 #elif defined(OS_MACOSX) && !defined(OS_IOS)
   ScopedRefCountedIOSurfaceMachPort mach_port;
 #endif
 };
 
 // This interface typically correspond to a type of shared memory that is also
 // shared with the GPU. A GPU memory buffer can be written to directly by
 // regular CPU code, but can also be read by the GPU.
 class GFX_EXPORT GpuMemoryBuffer {
@@ skipping 40 matching lines @@
 
 // Returns an instance of |handle| which can be sent over IPC. This duplicates
 // the file-handles as appropriate, so that the IPC code take ownership of them,
 // without invalidating |handle| itself.
 GFX_EXPORT GpuMemoryBufferHandle
 CloneHandleForIPC(const GpuMemoryBufferHandle& handle);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GPU_MEMORY_BUFFER_H_