[Android] Ignore status from non tracked activities

When activity_1 start activity_2(contains XWalkView), ApplicationStatus will start tracking when XWalkView initialized,
But ApplicationStatus will receive status such as onStop from activity_1, we do not need track activity_1, just ignore it.
For upstream, there is no such kind of case, ApplicationStatus will track all activities inside the package.

BUG=XWALK-1454
Merge pull request #147 from kurli/embedded-fail

[Android] Ignore status from non tracked activities