This test demonstrates that it is only the "root" conjuncts within a
pattern that need to be ignored for the purpose of identifying
redundant conjuncts, and not any of their children.

Thus `b` can be simplified, provided `b.w` survives, which is enough
to ensure it matches the pattern.

See also 61.

-- a.cue --
a: [string]: {
	x: y: z: 5
}
b: w: x: y: {}
b: a
-- out/trim-v3 --
== a.cue
a: [string]: {
	x: y: z: 5
}
b: w: _
b: a
-- diff/-out/trim-v3<==>+out/trim --
diff old new
--- old
+++ new
@@ -2,5 +2,5 @@
 a: [string]: {
 	x: y: z: 5
 }
-b: w: x: y: {}
+b: w: _
 b: a
-- out/trim-v3-noshare --
== a.cue
a: [string]: {
	x: y: z: 5
}
b: w: _
b: a
-- diff/-out/trim-v3-noshare<==>+out/trim --
diff old new
--- old
+++ new
@@ -2,5 +2,5 @@
 a: [string]: {
 	x: y: z: 5
 }
-b: w: x: y: {}
+b: w: _
 b: a
-- out/trim --
== a.cue
a: [string]: {
	x: y: z: 5
}
b: w: x: y: {}
b: a
