Migrated some windowing methods from StackId to WindowConfiguration

First pass at transitioning away from using stack ids for windowing mode
to WindowConfiguration. Added some TODO that will require the introduction
of applicationType in WindowConfiguration before additional conversation
can be done.

Test: bit FrameworksServicesTests:com.android.server.wm.WindowConfigurationTests
Test: adb shell am instrument -w -e package com.android.server.wm com.android.frameworks.servicestests/android.support.test.runner.AndroidJUnitRunner
Test: go/wm-smoke
Change-Id: I2b315623faa16445a9f942e082089123842cb5a1