App_list: Update Search Result Page View's OnBoundsChanged to reset rect based...

App_list: Update Search Result Page View's OnBoundsChanged to reset rect based on size instead of size and origin.

Bug: 1010724
Change-Id: Ic6061f243942a5c1d835f0df002321ee46fba78a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1841574
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703498}

ash/app_list/views/search_result_page_view.cc

@@ -268,10 +268,11 @@ gfx::Size SearchResultPageView::CalculatePreferredSize() const {
 }
 
 void SearchResultPageView::OnBoundsChanged(const gfx::Rect& previous_bounds) {
-  // This bounds change is produced by search result movement (rotation, etc)
-  // and all content has to follow.
-  if (previous_bounds != GetContentsBounds())
-    layer()->SetClipRect(GetContentsBounds());
+  // The clip rect set for page state animations needs to be reset when the
+  // bounds change because page size change invalidates the previous bounds.
+  // This allows content to properly follow target bounds when screen rotates.
+  if (previous_bounds.size() != bounds().size())
+    layer()->SetClipRect(gfx::Rect());
 }
 
 void SearchResultPageView::ReorderSearchResultContainers() {