Merge "Store process of window in Session" into main

services/core/java/com/android/server/wm/Session.java

services/core/java/com/android/server/wm/WindowState.java

...mtests/src/com/android/server/wm/ActivityRecordTests.java

.../com/android/server/wm/BackNavigationControllerTests.java

...ts/wmtests/src/com/android/server/wm/DisplayAreaTest.java

...mtests/src/com/android/server/wm/DisplayContentTests.java

...ts/src/com/android/server/wm/DragDropControllerTests.java

...ts/wmtests/src/com/android/server/wm/SizeCompatTests.java

.../src/com/android/server/wm/WindowManagerServiceTests.java

...s/wmtests/src/com/android/server/wm/WindowStateTests.java

...ts/wmtests/src/com/android/server/wm/WindowTestsBase.java