Support content URIs w/ userId in IC#commitContent

With this CL, one can specify a content URI with an embedded user ID to
InputContentInfo, like such a URI is supported in
Context#grantUriPermission().

Note that such a scenario is actually possible when 1) an application
running as User X sets a content URI to the system clipboard then 2) the
IME runing as User Y who share the clipboard with User X obtains the
content URI from the system and tries to create a new instance of
InputContentInfo.

Bug: 32427307
Bug: 32778718
Test: 'adb shell dumpsys activity permissions' with a custom IME that
      instantiates InputContentInfo from the content URI obtained from
      the clipboard.
Change-Id: I7918c0a379b8f3e7e64b106447b42447876f9057