Backport commit to fix a crash in Android < 4.0.3.

Commit cherry-picked from the 3.6.x branch, original message:

>  CB-7265 Fix crash when navigating to custom protocol (introduced in 3.5.1)
>
>  Conflicts:
>	framework/src/org/apache/cordova/CordovaUriHelper.java
>
>  Github: close #111

This fixes a regression introduced by the 3.5.1 security fixes that cause a crash in Android < 4.0.3 when the webview is redirected to a custom URL scheme.

Apache issue: https://issues.apache.org/jira/browse/CB-7265