Workaround for ignored resizeableActivity param

If <uses-sdk> tag is below <application> in AndroidManifest.xml then,
when activity is parsed, targetSdkVersion param is not yet set correctly.
Because of that we're defaulting to RESIZE_MODE_FORCE_RESIZEABLE and the
param resizeableActivity will be ignored.
This CL checks if resizeableActivity was set explicitly when targetSdkVersion
is less than N (or not set).

Bug: 28020462
Change-Id: I099f6c00dd50547ddea873e47dbb447869d0be6f