Fully (?) fix overflow: auto with delayed scroll updates

third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html

Index: third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html
diff --git a/third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html b/third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html
index b031fb30ae81b686f6d9e13ce188444d1e471386..436b2d13b5afdc08c9175da6151030ae562f2618 100644
--- a/third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html
+++ b/third_party/WebKit/LayoutTests/css3/flexbox/overflow-auto-resizes-correctly.html
@@ -19,6 +19,7 @@
 }
 .vbox {
   overflow-y: auto;
+  max-height: 200px;

[cbiesinger, 2016/02/25 20:46:26]

I made this change because I am no longer sure that the testcase was correct. I
don't think a reasonable flexbox implementation can produce the expected result,
because to get that result you need to apply the stretched height from the
flexbox layout first, then lay out the object and notice the overflow.

At any rate, the changed CSS still tests what the original was meant to test,
afaict.

IE 11 and FF (yesterday's nightly) did not match us here.

 }
 .intrinsic-height-box {
   min-height: -webkit-min-content;
@@ -76,11 +77,9 @@
   var scrollbarSize = measure.offsetWidth - measure.clientWidth;
   shouldNotBe("scrollbarSize", "0");
 
-  // TODO(cbiesinger): These should really be 100 and 100 + scrollbarSize, but
-  // we currently have a bug that makes it not so.
   var inner = document.getElementById('inner');
-  shouldBe("inner.clientWidth", "100 - scrollbarSize");
-  shouldBe("inner.offsetWidth", "100");
+  shouldBe("inner.clientWidth", "100");
+  shouldBe("inner.offsetWidth", "100 + scrollbarSize");
 
   var vbox = document.querySelector('.vbox');
   shouldBe("vbox.clientWidth", "100");