Account for perspective of the scroller when determining a transformed
child's contribution to layout overflow.

Bug: 723788
Change-Id: I18902203e16b058d3f2fa715c10605ebf8a50d36
Reviewed-on: https://chromium-review.googlesource.com/539059
Commit-Queue: Chris harrelson <[email protected]>
Reviewed-by: Tien-Ren Chen <[email protected]>
Cr-Commit-Position: refs/heads/master@{#482101}
diff --git a/third_party/WebKit/LayoutTests/overflow/overflow-transform-perspective.html b/third_party/WebKit/LayoutTests/overflow/overflow-transform-perspective.html
new file mode 100644
index 0000000..172e1022
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/overflow/overflow-transform-perspective.html
@@ -0,0 +1,19 @@
+<!doctype HTML>
+<style>
+.container {
+  width: 100px;
+  height: 100px;
+  perspective: 100px;
+  overflow: scroll;
+}
+.target {
+  transform: rotateY(-45deg);
+  width: 90px;
+  height: 80px;
+  background-image: linear-gradient(to right, red 0% ,green 50% , blue 50%);
+}
+</style>
+The result should have horizontal and vertical scrollbars.
+<div class="container" style="">
+  <div class="target"></div>
+</div>