Add infrastructure for partial layouts

LayoutTests/fast/dom/partial-layout-block-expected.txt

Index: LayoutTests/fast/dom/partial-layout-block-expected.txt
diff --git a/LayoutTests/fast/dom/partial-layout-block-expected.txt b/LayoutTests/fast/dom/partial-layout-block-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..4ed444a5292e93a1c42e5810abcad11aa6d04184
--- /dev/null
+++ b/LayoutTests/fast/dom/partial-layout-block-expected.txt
@@ -0,0 +1,20 @@
+Test that partial layout works for offset{width, height, left, top} methods.
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS successfullyParsed is true
+
+TEST COMPLETE
+WARN: shouldBe() expects string arguments

[eseidel, 2013/09/03 18:16:08]

Looks wrong.

[pdr., 2013/09/03 21:37:35]

Fixed, I moved all of these off the test-pre/test-post harness and onto
testharness.js. The former requires strings :/

+PASS 780 is document.body.offsetWidth - 20
+WARN: shouldBe() expects string arguments
+PASS 120 is measure.offsetHeight
+WARN: shouldBe() expects string arguments
+PASS 139 is 139
+WARN: shouldBe() expects string arguments
+PASS 10 is measure.offsetLeft
+PASS successfullyParsed is true
+
+TEST COMPLETE
+