Selector: Backport jQuery selection context logic to selector-native

This makes:
```js
$div.find("div > *")
```
no longer matching children of `$div`.

Also, leading combinators now work, e.g.:
```js
$div.find( "> *" );
```
returns children of `$div`.

As a result of that, a number of tests are no longer skipped in the
`selector-native` mode.

Also, rename `rcombinators` to `rleadingCombinator`.

Fixes gh-5185
Closes gh-5186
Ref gh-5085

1 files changed, 3 insertions, 0 deletions

diff --git a/src/selector/var/rpseudo.js b/src/selector/var/rpseudo.js
new file mode 100644
index 000000000..9ed943a5f
--- /dev/null
+++ b/src/selector/var/rpseudo.js
@@ -0,0 +1,3 @@
+import pseudos from "./pseudos.js";
+
+export default new RegExp( pseudos );