gfx: Use unsigned strides for gpu memory buffers.

gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc

Index: gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc
diff --git a/gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc b/gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc
index 86855a8a3ddefd95d8dcb09454d3c0e1219f03e3..d050eb3ee326aec4cec7ed3cde2ec4b7b6c88c27 100644
--- a/gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc
+++ b/gpu/ipc/client/gpu_memory_buffer_impl_ozone_native_pixmap.cc
@@ -123,9 +123,9 @@ void GpuMemoryBufferImplOzoneNativePixmap::Unmap() {
   data_ = nullptr;
 }
 
-int GpuMemoryBufferImplOzoneNativePixmap::stride(size_t plane) const {
+uint32_t GpuMemoryBufferImplOzoneNativePixmap::stride(size_t plane) const {
   DCHECK_LT(plane, gfx::NumberOfPlanesForBufferFormat(format_));
-  int stride;
+  uint32_t stride;
   pixmap_->GetStride(&stride);
   return stride;
 }