Report non-fixed orientation for resizable locked orientation

The "locked" orientation can be used to preserve current display
orientation. But when resolving activity bounds, the size should
not be restricted to portrait or landscape for app with target
sdk 36 on large screen.

Bug: 409503877
Flag: com.android.window.flags.universal_resizable_by_default
Test: SizeCompatTests#testUniversalResizeableByDefault
Test: adb shell am compat enable UNIVERSAL_RESIZABLE_BY_DEFAULT $pkg
      Launch the activity with resizeableActivity="false"
      and screenOrientation="locked".
      Make the activity enter split screen.
      The activity should not have letterbox.

Change-Id: I0c2d5a2a8785358568ca534233bf2bf830e567b7