gfx: Use unsigned strides for gpu memory buffers.

ui/gfx/native_pixmap_handle_ozone.h

 // Copyright 2015 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_NATIVE_PIXMAP_HANDLE_OZONE_H_
 #define UI_GFX_NATIVE_PIXMAP_HANDLE_OZONE_H_
 
 #include <stdint.h>
 #include <vector>
 
 #include "base/file_descriptor_posix.h"
 #include "ui/gfx/gfx_export.h"
 
 namespace gfx {
 
 // NativePixmapPlane is used to carry the plane related information for GBM
 // buffer. More fields can be added if they are plane specific.
 struct GFX_EXPORT NativePixmapPlane {
   NativePixmapPlane();
-  NativePixmapPlane(int stride, int offset, uint64_t modifier);
+  NativePixmapPlane(uint32_t stride, uint32_t offset, uint64_t modifier);
   NativePixmapPlane(const NativePixmapPlane& other);
   ~NativePixmapPlane();
 
   // The strides and offsets in bytes to be used when accessing the buffers via
   // a memory mapping. One per plane per entry.
-  int stride;
-  int offset;
+  uint32_t stride;
+  uint32_t offset;
   // The modifier is retrieved from GBM library and passed to EGL driver.
   // Generally it's platform specific, and we don't need to modify it in
   // Chromium code. Also one per plane per entry.
   uint64_t modifier;
 };
 
 struct GFX_EXPORT NativePixmapHandle {
   NativePixmapHandle();
   NativePixmapHandle(const NativePixmapHandle& other);
 
   ~NativePixmapHandle();
   // File descriptors for the underlying memory objects (usually dmabufs).
   std::vector<base::FileDescriptor> fds;
 
   std::vector<NativePixmapPlane> planes;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_NATIVE_PIXMAP_HANDLE_OZONE_H_