Allow modifiers to specify windowing mode and preferred display.

Allow modifiers to specify windowing mode and preferred display.

This changelist extends the parameters that positioners can
provide to include the windowing mode and display for a stack to
launch into. These are provided via the LaunchingParams object, which
replaces the previous bounds Rect as the result. When the values are
provided when laying out a task, the Controller will apply the
result. In other cases, such as in ActivityStarter, the caller of
LaunchingBoundsController#calculate is responsible applying the
result.

Fixes: 70031444
Test: atest FrameworksServicesTests:LaunchingBoundsControllerTests#testLayoutTaskPreferredDisplayChange
Test: atest FrameworksServicesTests:LaunchingBoundsControllerTests#testLayoutTaskWindowingModeChange
Change-Id: I949e2b5047663bfc297aac654f365109f0b1feb1