Add css-snappoints-1.vim and tests

test/test.css

@@ -473,6 +473,14 @@
   display: contain-floats;
 }
 
+.snappoints {
+  scroll-snap-type: mandatory;
+  scroll-snap-points-x: proximity;
+  scroll-snap-points-y: auto;
+  scroll-snap-destination: auto;
+  scroll-snap-coordinate: auto;
+}
+
 .speech {
   voice-volume: 10dB;
   voice-balance: literal-punctuation;

test/test.html

@@ -520,6 +520,15 @@
 }
 </style>
 <style>
+.snappoints {
+  scroll-snap-type: mandatory;
+  scroll-snap-points-x: proximity;
+  scroll-snap-points-y: auto;
+  scroll-snap-destination: auto;
+  scroll-snap-coordinate: auto;
+}
+</style>
+<style>
 .speech {
   voice-volume: 10dB;
   voice-balance: literal-punctuation;