Route selection bounds updates through WebLayerTreeView

Source/web/tests/data/composited_selection_bounds_transformed.html

+<style>
+    @font-face {
+        font-family: ahem;
+        src: url(Ahem.ttf);
+    }
+    * {
+        font-family: ahem;
+    }
+    #text {
+        transform: rotate(30deg);

[chrishtr, 2014/09/19 00:17:42]

Is the code supposed to do something reasonable for a 3D rotation? What should
it do?

[trchen, 2014/09/19 00:28:12]

Actually 2D transform is the more difficult case here. :)

With 3D transform it simply creates a layer and the selection bound shall return
untransformed coordinates. This was tested in
composited_selection_bounds_split_layer.html although it is a degenerated
example.

[chrishtr, 2014/09/19 00:47:41]

Ah right. :)

+    }
+</style>
+<div id="text">The quick brown fox jumped over the lazy dog.</div>
+<script>
+    var range = document.createRange();
+    var textNode = document.getElementById("text").firstChild;
+    range.setStart(textNode, 10);
+    range.setEnd(textNode, 25);
+    document.getSelection().addRange(range);
+
+    window.expectedResult = [document, 157, -87, 151, -77, document, 313, 3, 307, 13];
+</script>
+