Allow touch adjustment to return Shadow DOM node.

LayoutTests/touchadjustment/resources/touchadjustment.js

Index: LayoutTests/touchadjustment/resources/touchadjustment.js
diff --git a/LayoutTests/touchadjustment/resources/touchadjustment.js b/LayoutTests/touchadjustment/resources/touchadjustment.js
index 2a3aa3d6716a82bb9f2589f1bbfbffadda3372e0..46a7142c1dc3a48746a264e62c5b4ef1d7b3cb9e 100644
--- a/LayoutTests/touchadjustment/resources/touchadjustment.js
+++ b/LayoutTests/touchadjustment/resources/touchadjustment.js
@@ -63,9 +63,30 @@ function shouldBeWithin(adjustedPoint, targetArea) {
     }
 }
 
-function testTouchPoint(touchpoint, targetNode, allowTextNodes)
+function shadowHost(node)
 {
-    var adjustedNode = internals.touchNodeAdjustedToBestClickableNode(touchpoint.left, touchpoint.top, touchpoint.width, touchpoint.height, document);
+    while (node != null) {
+        // Not exactly the best method of detecting shadow root as other things can have a document fragment too.

[Rick Byers, 2014/07/10 20:09:10]

You could just look for the presence of the 'host' property, right?  If it's not
there than keep going up.  Returning null for a documentFragment with no hose
seems completely reasonable.

[Zeeshan Qureshi, 2014/07/10 20:46:16]

Done.

+        if (node.nodeType == 11)
+            return node.host;
+        node = node.parentNode;
+    }
+    return node;
+}
+
+function touchNodeAdjustedToBestClickableNode(left, top, width, height, doc, disallowShadowDOM)

[Rick Byers, 2014/07/10 20:09:10]

nit: rather than add this new function, might as well put this logic into
testTouchPoint (since it's conceptually the same as allowTextNodes), right?

[Zeeshan Qureshi, 2014/07/10 20:46:16]

The only reason to keep that was because nested-shadow-node.html was not using
testTouchPoint, but you're right, switching to that makes this cleaner.

+{
+    var adjustedNode = internals.touchNodeAdjustedToBestClickableNode(left, top, width, height, doc);
+    if (disallowShadowDOM && adjustedNode && adjustedNode.nodeType == 1) {
+        while (shadowHost(adjustedNode))
+            adjustedNode = shadowHost(adjustedNode);
+    }
+    return adjustedNode;
+}
+
+function testTouchPoint(touchpoint, targetNode, allowTextNodes, disallowShadowDOM)
+{
+    var adjustedNode = touchNodeAdjustedToBestClickableNode(touchpoint.left, touchpoint.top, touchpoint.width, touchpoint.height, document, disallowShadowDOM);
     if (!allowTextNodes && adjustedNode && adjustedNode.nodeType == 3)
         adjustedNode = adjustedNode.parentNode;
     shouldBeNode(adjustedNode, targetNode);