gfx: Use unsigned strides for gpu memory buffers.

ui/gfx/native_pixmap_handle_ozone.cc

Index: ui/gfx/native_pixmap_handle_ozone.cc
diff --git a/ui/gfx/native_pixmap_handle_ozone.cc b/ui/gfx/native_pixmap_handle_ozone.cc
index 8bd17bcb6ac62f8c6480ccea73fe40c584061d4c..44b8955628a93f49200ac51cd710aa565abcf1c0 100644
--- a/ui/gfx/native_pixmap_handle_ozone.cc
+++ b/ui/gfx/native_pixmap_handle_ozone.cc
@@ -8,7 +8,9 @@ namespace gfx {
 
 NativePixmapPlane::NativePixmapPlane() : stride(0), offset(0), modifier(0) {}
 
-NativePixmapPlane::NativePixmapPlane(int stride, int offset, uint64_t modifier)
+NativePixmapPlane::NativePixmapPlane(uint32_t stride,
+                                     uint32_t offset,
+                                     uint64_t modifier)
     : stride(stride), offset(offset), modifier(modifier) {}
 
 NativePixmapPlane::NativePixmapPlane(const NativePixmapPlane& other) = default;