Toolbar: Fix a bug with 3rd-party search vendor

The search box scroll listener needs updating whenever search engine
provider changes. It was prevented by a small optimization
introduced in https://crrev.com/c/2500389 which updates the listener
only when there's a new visible NTP. This CL fixes the bug by removing
the line added in the culprit CL.

Bug: 1145981
Change-Id: I674d82546e5bf9f2067cf26f3413c57bf8dc35b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2521977Reviewed-by: Filip Gorski <fgorski@chromium.org>
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#825224}

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarManager.java

@@ -813,7 +813,6 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
         @Override
         public void setSearchBoxScrollListener(Callback<Float> scrollCallback) {
             NewTabPage newVisibleNtp = getNewTabPageForCurrentTab();
-            if (mVisibleNtp == newVisibleNtp) return;
             if (mVisibleNtp != null) mVisibleNtp.setSearchBoxScrollListener(null);
             mVisibleNtp = newVisibleNtp;
             if (mVisibleNtp != null && shouldUpdateListener()) {
@@ -867,6 +866,12 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
             };
         } else if (toolbarLayout instanceof ToolbarTablet) {
             return new ToolbarNtpDelegate() {
+                @Override
+                public void setSearchBoxScrollListener(Callback<Float> scrollCallback) {
+                    if (mVisibleNtp == getNewTabPageForCurrentTab()) return;
+                    super.setSearchBoxScrollListener(scrollCallback);
+                }
+
                 @Override
                 protected boolean shouldUpdateListener() {
                     return true;