Make aborted commits inform the scroll delegate.

cc/layers/layer_impl_unittest.cc

Index: cc/layers/layer_impl_unittest.cc
diff --git a/cc/layers/layer_impl_unittest.cc b/cc/layers/layer_impl_unittest.cc
index 99673f6146b7495e83cbf4279c58cf2308d6698f..725573d514c378d72ecfa27698575a48d8698602 100644
--- a/cc/layers/layer_impl_unittest.cc
+++ b/cc/layers/layer_impl_unittest.cc
@@ -497,7 +497,13 @@ TEST_F(LayerImplScrollTest, ScrollByWithNonZeroOffset) {
 
 class ScrollDelegateIgnore : public LayerImpl::ScrollOffsetDelegate {
  public:
-  void SetTotalScrollOffset(const gfx::ScrollOffset& new_value) override {}
+  void SetTotalScrollOffset(const gfx::ScrollOffset& new_value) override {
+    last_attempted_set_offset_ = new_value;
+  }
+  gfx::ScrollOffset last_attempted_set_offset() const {
+    return last_attempted_set_offset_;
+  }
+
   gfx::ScrollOffset GetTotalScrollOffset() override {
     return gfx::ScrollOffset(fixed_offset_);
   }
@@ -509,6 +515,7 @@ class ScrollDelegateIgnore : public LayerImpl::ScrollOffsetDelegate {
   }
 
  private:
+  gfx::ScrollOffset last_attempted_set_offset_;
   gfx::Vector2dF fixed_offset_;
 };
 
@@ -632,6 +639,8 @@ TEST_F(LayerImplScrollTest, ApplySentScrollsWithIgnoringDelegate) {
 
   layer()->ApplySentScrollDeltasFromAbortedCommit();
 
+  EXPECT_VECTOR_EQ(fixed_offset, delegate.last_attempted_set_offset());
+
   EXPECT_VECTOR_EQ(fixed_offset, layer()->TotalScrollOffset());
   EXPECT_VECTOR_EQ(gfx::ScrollOffsetWithDelta(scroll_offset, sent_scroll_delta),
                    layer()->scroll_offset());