Re-add some code I accidentally deleted in ChromeTabbedActivity.java

When I added the incognito toggle button in
https://chromium-review.googlesource.com/1060560, I inadvertently removed some
code from ChromeTabbedActivity#toggleOverview() for reasons I don't recall. This
is now resulting in odd behavior occurring if you tab the tab switcher button
immediately after selecting the "close all tabs" menu item.

This CL re-adds the code I inadvertently removed and fixes this bug.

Bug: 851971
Change-Id: I9c2e5a713c9528f05b7d12938246d44c406ad3d7
Reviewed-on: https://chromium-review.googlesource.com/1101819Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: Ryan Landay <rlanday@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567442}

chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java

@@ -58,6 +58,7 @@ import org.chromium.chrome.browser.browseractions.BrowserActionsService;
 import org.chromium.chrome.browser.browseractions.BrowserActionsTabModelSelector;
 import org.chromium.chrome.browser.compositor.CompositorViewHolder;
 import org.chromium.chrome.browser.compositor.layouts.Layout;
+import org.chromium.chrome.browser.compositor.layouts.LayoutManager;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManagerChrome;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManagerChromePhone;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManagerChromeTablet;
@@ -1857,6 +1858,10 @@ public class ChromeTabbedActivity
             getCompositorViewHolder().hideKeyboard(() -> mLayoutManager.showOverview(true));
             updateAccessibilityState(false);
         } else {
+            Layout activeLayout = mLayoutManager.getActiveLayout();
+            if (activeLayout instanceof StackLayout) {
+                ((StackLayout) activeLayout).commitOutstandingModelState(LayoutManager.time());
+            }
             if (getCurrentTabModel().getCount() != 0) {
                 // Don't hide overview if current tab stack is empty()
                 mLayoutManager.hideOverview(true);