Temporarily disable smooth-scroll-for-find on Android

After enabling smooth-scroll-for-find on Android, tapping "find"
wouldn't scroll the text into view. To fix the regression, we would
temporarily disable the smooth behavior, and re-enable it after we
have solved the problem.

Bug: 839795
Change-Id: I7733a269b5ee830df4352f10cdb9b036f4c779f2
Reviewed-on: https://chromium-review.googlesource.com/1069112Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560920}

content/public/common/web_preferences.cc

@@ -158,7 +158,9 @@ WebPreferences::WebPreferences()
       shrinks_viewport_contents_to_fit(true),
       viewport_style(ViewportStyle::MOBILE),
       always_show_context_menu_on_touch(false),
-      smooth_scroll_for_find_enabled(true),
+      // TODO(sunyunjia): Re-enable smooth scroll for find on Android.
+      // https://crbug.com/845500
+      smooth_scroll_for_find_enabled(false),
 #else
       viewport_meta_enabled(false),
       shrinks_viewport_contents_to_fit(false),