servo: Merge #12263 - Make geckolib possible to build on stable Rust (from servo:stable-geckolib); r=nox

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More for servo/servo#11815

r? nox

---
<!-- 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
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because _____

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Source-Repo: https://github.com/servo/servo
Source-Revision: 3d557b6f25eb9dbd084cb53bbc9a9cf93bad825b

UltraBlame original commit: 0563b21dfecef0e2f3f04f56f4f108a5dcbe85ec

Author: marco-c

servo/components/style/keyframes.rs

@@ -137,8 +137,22 @@ Copy
 Clone
 PartialEq
 PartialOrd
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct
@@ -448,8 +462,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct
@@ -538,8 +566,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct
@@ -752,8 +794,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 enum
@@ -789,8 +845,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct
@@ -920,8 +990,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct

servo/components/style/properties/helpers.mako.rs

@@ -1633,8 +1633,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct

servo/components/style/properties/helpers/animated_properties.mako.rs

@@ -469,8 +469,22 @@ Copy
 Clone
 Debug
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 enum
@@ -831,8 +845,22 @@ derive
 Clone
 Debug
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 enum

servo/components/style/properties/longhand/box.mako.rs

@@ -4562,8 +4562,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct
@@ -5016,8 +5030,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 enum
@@ -5109,8 +5137,22 @@ derive
 Debug
 Clone
 PartialEq
+)
+]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
 HeapSizeOf
 )
+)
 ]
 pub
 struct

servo/components/style/stylesheets.rs

@@ -539,10 +539,24 @@ KeyframesRule
 derive
 (
 Debug
-HeapSizeOf
 PartialEq
 )
 ]
+#
+[
+cfg_attr
+(
+feature
+=
+"
+servo
+"
+derive
+(
+HeapSizeOf
+)
+)
+]
 pub
 struct
 KeyframesRule

servo/ports/geckolib/Cargo.toml

@@ -116,6 +116,11 @@ servo_features
 heapsize
 "
 "
+selectors
+/
+unstable
+"
+"
 style
 /
 servo
@@ -255,22 +260,11 @@ num_cpus
 "
 selectors
 =
-{
-version
-=
 "
 0
 .
 6
 "
-features
-=
-[
-"
-unstable
-"
-]
-}
 smallvec
 =
 "