Hit test SVG line boxes

third_party/WebKit/LayoutTests/svg/hittest/text-dominant-baseline-hanging.svg

+<svg onload="runTest()" width="500" height="150" viewBox="0 0 1000 300" xmlns="http://www.w3.org/2000/svg">
+    <text id="text" dominant-baseline="hanging" x="10" y="10">Foo</text>
+    <defs>
+        <style type="text/css">
+        <![CDATA[
+            @font-face {
+                font-family: Ahem;

[fs, 2015/11/17 09:47:49]

I guess we should use the ahem.js helper or there will be flakes
(eventually?)...

[pdr., 2015/11/17 21:51:23]

Done

+                src: url(../../resources/Ahem.ttf);
+            }
+            text {
+                font-family: Ahem;
+                font-size: 40px;
+            }
+            ]]>
+        </style>
+        <script type="text/javascript">
+        <![CDATA[
+            function runTest() {
+                if (window.testRunner)
+                    testRunner.dumpAsText();
+
+                // The point at 15,15 is contained within the text's bounding box.

[fs, 2015/11/17 09:47:49]

This goes for the comments in all tests pretty much...

"...is contained within the <object>'s bounding box." is a fairly confusing
statement for a CL that makes sure the "bounding box" is not what's used to test
for intersections. More accurate would be something like:

"...is contained within a glyph cell of <object>."

(Preferably even which glyph cell, but I suppose we can punt on that level of
fidelity...)

[pdr., 2015/11/17 21:51:23]

Done

+                var text = document.getElementById("text");
+                if (document.elementFromPoint(15, 15) === text)
+                    text.textContent = "PASS";
+                else
+                    text.textContent = "FAIL";
+            }
+        ]]>
+        </script>
+    </defs>
+</svg>