Use fallback URL more extensively
Currently, if you type a URL in the omnibox, and if the URL gets redirected
to a 'intent://' URL, then it does not launch a native app and it just gets
ignored.
I believe that this is for security / UI reasons (see crbug.com/331571),
but it is somewhat weird that your URL (e.g. http://goo.gl/ABCDE) gets
completely ignored, especially when you aren't sure whether goo.gl will be
redirected to a normal URL or to an intent URL.
This behavior can be improved for the case when fallback URL is used,
as we can load the fallback URL instead of ignoring the URL.
Also there are other cases fallback URL can be useful, such as when
Context#startActivityIfNeeded() returns false.
BUG=470722
Review URL: https://codereview.chromium.org/
1039013002
Cr-Commit-Position: refs/heads/master@{#323162}