go/internal/gcimporter,cmd/compile: minor clean-up in iimport.go

Make two superficial fixes to iimport.go: rename instType to
instanceType (suggested in CL 349949), and fix a stale comment.

Done in both go/internal/gcimporter and cmd/compile/internal/importer.

Change-Id: Idfdda11a59b036a35824bbb1c101cba3652aeff4
Reviewed-on: https://go-review.googlesource.com/c/go/+/350031
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
diff --git a/src/cmd/compile/internal/importer/iimport.go b/src/cmd/compile/internal/importer/iimport.go
index 7f7143d..a92720d 100644
--- a/src/cmd/compile/internal/importer/iimport.go
+++ b/src/cmd/compile/internal/importer/iimport.go
@@ -72,7 +72,7 @@
 	structType
 	interfaceType
 	typeParamType
-	instType
+	instanceType
 	unionType
 )
 
@@ -646,7 +646,7 @@
 		r.p.doDecl(pkg, name)
 		return r.p.tparamIndex[id]
 
-	case instType:
+	case instanceType:
 		if r.p.exportVersion < iexportVersionGenerics {
 			errorf("unexpected instantiation type")
 		}
@@ -661,7 +661,7 @@
 		baseType := r.typ()
 		// The imported instantiated type doesn't include any methods, so
 		// we must always use the methods of the base (orig) type.
-		// TODO provide a non-nil *Checker
+		// TODO provide a non-nil *Environment
 		t, _ := types2.Instantiate(nil, baseType, targs, false)
 		return t
 
diff --git a/src/go/internal/gcimporter/iimport.go b/src/go/internal/gcimporter/iimport.go
index d9174d4..f570aab 100644
--- a/src/go/internal/gcimporter/iimport.go
+++ b/src/go/internal/gcimporter/iimport.go
@@ -72,7 +72,7 @@
 	structType
 	interfaceType
 	typeParamType
-	instType
+	instanceType
 	unionType
 )
 
@@ -638,7 +638,7 @@
 		r.p.doDecl(pkg, name)
 		return r.p.tparamIndex[id]
 
-	case instType:
+	case instanceType:
 		if r.p.exportVersion < iexportVersionGenerics {
 			errorf("unexpected instantiation type")
 		}
@@ -653,7 +653,7 @@
 		baseType := r.typ()
 		// The imported instantiated type doesn't include any methods, so
 		// we must always use the methods of the base (orig) type.
-		// TODO provide a non-nil *Checker
+		// TODO provide a non-nil *Environment
 		t, _ := types.Instantiate(nil, baseType, targs, false)
 		return t