Handle exceptions from #requestPermission()

This is a follow up CL to my previous CL [1] that let
IInputConnectionWrapper to call InputContentInfo#requestPermission()
automatically so that temporary URI permissions can be granted
automatically on API 25+ devices whenever
INPUT_CONTENT_GRANT_READ_URI_PERMISSION is specified.

However, in that CL we forgot to handle exceptions thrown from
InputContentInfo#requestPermission().  This is problematic because it is
actually easy for IMEs to cause SecurityException by specifying a
content URI that does not allow grantUriPermission, e.g.:

  inputConnection.commitContent(
          new InputContentInfo(Uri.parse("content://call_log/test"),
          new ClipDescription("test", new String[]{"image/gif"}));

As a result, IMEs can let the application crash at any time because
InputContentInfo#requestPermission() is automatically called inside the
Framework.

This CL makes sure that exceptions thrown from
InputContentInfo#requestPermission() can be handled gracefully.

 [1]: Id955435dd2e72549ee7134f46b3c6951581694ad
      f3806f57

Bug: 32162481
Change-Id: I08916a1f54518390d3b67ab1673dc901e3f9716a