Auto merge of #13456 - Wafflespeanut:warnings, r=emilio

Silence some warnings in geckolib

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---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors

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- [x] These changes do not require tests because it's a cleanup

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We'll be silencing thousands of warnings this way, which would probably help with Travis.

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components/style/gecko/selector_impl.rs

@@ -61,7 +61,7 @@ impl PseudoElement {
     }
 
     #[inline]
-    fn from_atom(atom: &WeakAtom, in_ua: bool) -> Option<Self> {
+    fn from_atom(atom: &WeakAtom, _in_ua: bool) -> Option<Self> {
         macro_rules! pseudo_element {
             ($pseudo_str_with_colon:expr, $atom:expr, $is_anon_box:expr) => {{
                 if atom == &*$atom {

components/style/gecko_bindings/mod.rs

@@ -2,17 +2,24 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#[allow(dead_code, non_camel_case_types)]
+#[allow(dead_code, improper_ctypes, non_camel_case_types)]
 pub mod bindings;
 pub mod ptr;
+
+// FIXME: We allow `improper_ctypes` (for now), because the lint doesn't allow
+// foreign structs to have `PhantomData`. We should remove this once the lint
+// ignores this case.
+
 #[cfg(debug_assertions)]
-#[allow(dead_code, non_camel_case_types, non_snake_case, non_upper_case_globals)]
+#[allow(dead_code, improper_ctypes, non_camel_case_types, non_snake_case, non_upper_case_globals)]
 pub mod structs {
     include!("structs_debug.rs");
 }
+
 #[cfg(not(debug_assertions))]
-#[allow(dead_code, non_camel_case_types, non_snake_case, non_upper_case_globals)]
+#[allow(dead_code, improper_ctypes, non_camel_case_types, non_snake_case, non_upper_case_globals)]
 pub mod structs {
     include!("structs_release.rs");
 }
+
 pub mod sugar;

components/style/gecko_bindings/sugar/ns_t_array.rs

@@ -6,7 +6,6 @@ use gecko_bindings::bindings;
 use gecko_bindings::structs::{nsTArray, nsTArrayHeader};
 use std::mem;
 use std::ops::{Deref, DerefMut};
-use std::os::raw::c_void;
 use std::slice;
 
 impl<T> Deref for nsTArray<T> {

components/style/gecko_string_cache/mod.rs

@@ -22,7 +22,7 @@ use std::ops::Deref;
 use std::slice;
 
 #[macro_use]
-#[allow(improper_ctypes, safe_extern_statics)]
+#[allow(improper_ctypes, non_camel_case_types)]
 pub mod atom_macro;
 #[macro_use]
 pub mod namespace;

components/style/properties/gecko.mako.rs

@@ -1118,7 +1118,6 @@ fn static_assert() {
         use gecko_bindings::structs::nsStyleImageLayers_Size_DimensionType;
         use gecko_bindings::structs::{nsStyleCoord_CalcValue, nsStyleImageLayers_Size};
         use properties::longhands::background_size::single_value::computed_value::T;
-        use values::computed::LengthOrPercentageOrAuto;
 
         let mut width = nsStyleCoord_CalcValue::new();
         let mut height = nsStyleCoord_CalcValue::new();