Sanitize selector Intent when handling intent: scheme.

Android Intents have a selector field which, if present, are used
to search for the Activity to invoke. These must also be sanitized
before handing off to the OS.

BUG:14562482
Change-Id: I30461e11be48ec623ab0f56d0d0f206dc2849c98
Merge tag 'android-4.4.4_r1' of https://android.googlesource.com/platform/frameworks/webview into kitkat

Android 4.4.4 Release 1