Update Traceur to check admin user status

This change updates Traceur to check for admin user privileges wherever
a developer options check occurs. This is intended to address the case
in which developer options (a global setting not differentiated on
current user privileges) being enabled would allow guest users to open
Traceur through a 3P app and view its trace files. This would previously
be possible even when ADB debugging was disabled by the admin user.

Traceur now listens for user changes so that its document root
(containing traces) is enabled/disabled based on the new user's admin

Test: Using ABTD, apply this on tm-dev+tm-qpr-dev, then check that:
      - There are no merge conflicts
      - CtsIntentSignatureTestCases passes (b/270791503)
      - TraceurUiTests passes
      Build+flash a local device on tm-dev+tm-qpr-dev and check that:
      - Traceur cannot be opened through 'am start' on a guest account
      - Opening Files on a guest account no longer shows a System Traces
        folder (even if Traceur's onCreate is somehow called)
      - System tracing no longer appears in settings for guests
Bug: 262243665
Bug: 262244249
Ignore-AOSP-First: Internal-first security fix
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:35b3591dc4e50d51d0d7b54eef6cc0c5c6260898)
Merged-In: I1c0c8c9588554378ae39a1a69a35ff44052b93e0
Change-Id: I1c0c8c9588554378ae39a1a69a35ff44052b93e0
8 files changed