Remove usage of unstable box syntax, except in the script crate

… because there’s a lot of it,
and script still uses any other unstable features anyway.

components/gfx/display_list/mod.rs

@@ -586,10 +586,10 @@ pub struct ClipScrollNode {
 
 impl ClipScrollNode {
     pub fn to_define_item(&self, pipeline_id: PipelineId) -> DisplayItem {
-        DisplayItem::DefineClipScrollNode(box DefineClipScrollNodeItem {
+        DisplayItem::DefineClipScrollNode(Box::new(DefineClipScrollNodeItem {
             base: BaseDisplayItem::empty(pipeline_id),
             node: self.clone(),
-        })
+        }))
     }
 }
 

components/gfx/lib.rs

@@ -4,7 +4,6 @@
 
 // For SIMD
 #![cfg_attr(any(target_os = "linux", target_os = "android"), feature(allocator_api))]
-#![feature(box_syntax)]
 #![feature(cfg_target_feature)]
 
 #![deny(unsafe_code)]

components/gfx/platform/freetype/font_context.rs

@@ -118,15 +118,15 @@ impl HeapSizeOf for FontContextHandle {
 
 impl FontContextHandle {
     pub fn new() -> FontContextHandle {
-        let user = Box::into_raw(box User {
+        let user = Box::into_raw(Box::new(User {
             size: 0,
-        });
-        let mem = Box::into_raw(box FT_MemoryRec_ {
+        }));
+        let mem = Box::into_raw(Box::new(FT_MemoryRec_ {
             user: user as *mut c_void,
             alloc: Some(ft_alloc),
             free: Some(ft_free),
             realloc: Some(ft_realloc),
-        });
+        }));
         unsafe {
             let mut ctx: FT_Library = ptr::null_mut();
 

components/gfx/text/shaping/harfbuzz.rs

@@ -509,7 +509,7 @@ extern fn font_table_func(_: *mut hb_face_t,
                 // `Box::into_raw` intentionally leaks the FontTable so we don't destroy the buffer
                 // while HarfBuzz is using it.  When HarfBuzz is done with the buffer, it will pass
                 // this raw pointer back to `destroy_blob_func` which will deallocate the Box.
-                let font_table_ptr = Box::into_raw(box font_table);
+                let font_table_ptr = Box::into_raw(Box::new(font_table));
 
                 let buf = (*font_table_ptr).buffer();
                 // HarfBuzz calls `destroy_blob_func` when the buffer is no longer needed.