Add tests for HTMLAreaElement coords/shape and processing model

third_party/WebKit/LayoutTests/fast/html/resources/hit-test.js

+setup({explicit_done: true});
+
+var img = document.getElementById('img');
+var area = document.getElementById('area');
+
+var hitRect = [[area, 3, 3], [area, 9, 9], [img, 1, 3], [img, 3, 1], [img, 11, 9], [img, 9, 11], [img, 21, 41], [img, 101, 101]];
+var hitNone = [[img, 3, 3], [img, 9, 9], [img, 1, 3], [img, 3, 1], [img, 11, 9], [img, 9, 11], [img, 21, 41], [img, 101, 101]];
+var hitAll = [[area, 1, 1], [area, 1, 299], [area, 299, 1], [area, 299, 299], [area, 21, 41], [area, 101, 101]];
+var hitCircle = [[area, 11, 40], [area, 29, 40], [area, 20, 31], [area, 20, 49], [img, 12, 32], [img, 28, 48], [img, 101, 101]];
+var hitPoly = [[area, 101, 101], [area, 119, 101], [area, 101, 119], [img, 118, 118], [img, 3, 3], [img, 21, 41]];
+var hitStar = [[area, 101, 101], [area, 199, 101], [area, 150, 51], [img, 150, 125], [img, 3, 3], [img, 21, 41]];
+
+var tests;
+// The test file should have `tests` defined as follows:
+// tests = [
+// {desc: string, shape: string?, coords: string?, hit: [[element, x, y], ...]},
+// ...
+// ];
+
+onload = function() {
+  tests.forEach(function(t) {
+    test(function(t_obj) {
+      if (area.shape === null) {
+        area.removeAttribute('shape');
+      } else {
+        area.shape = t.shape;
+      }
+      if (area.coords === null) {
+        area.removeAttribute('coords');
+      } else {
+        area.coords = t.coords;
+      }
+      t.hit.forEach(function(arr) {
+        var expected = arr[0];
+        var x = arr[1];
+        var y = arr[2];
+        assert_equals(document.elementFromPoint(x, y), expected, 'elementFromPoint('+x+', '+y+')');
+      });
+    }, t.desc + ': ' + format_value(t.coords) + ' (' + t.shape + ')');
+  });
+  done();
+};