Don't remove entries for overriddable modules

Previously, when there is apex_set that is overriding another module,
the entry for the overridden module is removed from apexkeys.txt.
However, this is wrong because the existence of the apex_set module
doesn't necessary mean that the module is insatalled instead of the
overridden module. That is determined by PRODUCT_PACKAGES which Soong
has no knowledge of. Therefore, we don't delete the entry for the
overridden (actually possibly overridable) modules in the file.

Bug: 158729168
Test: m
Change-Id: I85d0c756f862323bae556bf657d66ec50038985f

apex/apex_test.go

@@ -4988,7 +4988,7 @@ func TestApexKeysTxt(t *testing.T) {
 	apexKeysText := ctx.SingletonForTests("apex_keys_text")
 	content := apexKeysText.MaybeDescription("apexkeys.txt").BuildParams.Args["content"]
 	ensureContains(t, content, `name="myapex_set.apex" public_key="PRESIGNED" private_key="PRESIGNED" container_certificate="PRESIGNED" container_private_key="PRESIGNED" partition="system"`)
-	ensureNotContains(t, content, "myapex.apex")
+	ensureContains(t, content, `name="myapex.apex" public_key="PRESIGNED" private_key="PRESIGNED" container_certificate="PRESIGNED" container_private_key="PRESIGNED" partition="system"`)
 }
 
 func TestMain(m *testing.M) {

apex/key.go

@@ -160,12 +160,6 @@ func (s *apexKeysText) GenerateBuildActions(ctx android.SingletonContext) {
 				presigned: true,
 				partition: m.PartitionTag(ctx.DeviceConfig()),
 			}
-
-			for _, om := range m.Overrides() {
-				if _, ok := apexKeyMap[om]; ok {
-					delete(apexKeyMap, om)
-				}
-			}
 			apexKeyMap[m.BaseModuleName()] = entry
 		}
 	})