Add filegroup support to notice property.

Also, replace all notice file references with the parent directory
pattern(../) with filegroups. This new version has
ALLOW_MISSING_DEPENDENCIES support, so shouldn't break branches that
don't contain the libwinpthread project.

Bug: 118899640
Test: Manual build + forrest runs on previously failed branches.
Change-Id: I13e70e8dab547f82c1c8f15eccc7ae116e480ad5
diff --git a/android/androidmk.go b/android/androidmk.go
index 6224361..18b26d9 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -317,8 +317,8 @@
 		}
 	}
 
-	if amod.commonProperties.Notice != nil {
-		fmt.Fprintln(&data.preamble, "LOCAL_NOTICE_FILE :=", "$(LOCAL_PATH)/"+*amod.commonProperties.Notice)
+	if amod.noticeFile != nil {
+		fmt.Fprintln(&data.preamble, "LOCAL_NOTICE_FILE :=", amod.noticeFile.String())
 	}
 
 	if host {