[RootLayerScrolls] Update test expectations

With RLS enabled, the LayoutView has additional scrolling and
scrolling contents layers.

BUG=711468
R=skobes@chromium.org

Change-Id: I052b329d82152fa05eeeccdbfd5823794f80eda4
Reviewed-on: https://chromium-review.googlesource.com/677084Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: Stefan Zager <szager@chromium.org>
Cr-Commit-Position: refs/heads/master@{#503599}

third_party/WebKit/LayoutTests/compositing/dont-composite-select-elements.html

@@ -13,6 +13,10 @@ if (window.internals)
 test(function() {
     var json = JSON.parse(window.internals.layerTreeAsText(document));
     // The <select> element's scroller should be painted into the root layer.
-    assert_equals(json["layers"].length, 1);
+    if (internals.runtimeFlags.rootLayerScrollingEnabled) {
+      assert_equals(json["layers"].length, 3);
+    } else {
+      assert_equals(json["layers"].length, 1);
+    }
     }, "test");
 </script>

third_party/WebKit/LayoutTests/compositing/dont-composite-text-input-elements.html

@@ -8,6 +8,10 @@ if (window.internals)
 test(function() {
     var json = JSON.parse(window.internals.layerTreeAsText(document));
     // The <input> element's scroller should be painted into the root layer.
-    assert_equals(json["layers"].length, 1);
+    if (internals.runtimeFlags.rootLayerScrollingEnabled) {
+      assert_equals(json["layers"].length, 3);
+    } else {
+      assert_equals(json["layers"].length, 1);
+    }
     }, "test");
 </script>