Add ContentProvider perf tests

Add a stub ContentProvider in ActivityManagerPerfTestsTestApp.
Add two tests for
Context.getContentResolver().acquireContentProviderClient(PKG_NAME),
one when target package is running, one when it isn't.

Test: m ActivityManagerPerfTestsTestApp ActivityManagerPerfTests
Test: adb install \
$OUT/data/app/ActivityManagerPerfTestsTestApp/ActivityManagerPerfTestsTestApp.apk
Test: adb install \
$OUT/data/app/ActivityManagerPerfTests/ActivityManagerPerfTests.apk
Test: adb shell am instrument -w -e class \
com.android.frameworks.perftests.am.tests.ContentProviderPerfTest \
com.android.frameworks.perftests.amtests/android.support.test.runner.AndroidJUnitRunner

BUG: 67460485

Change-Id: Ia979832436a0d3923f6569bc52d22f17bb612a0e