track static deps when gatherint notices for apex

This change fixes a bug that license info for statically linked
libraries are absent in the merged notice for APEX. The problem was that
we were iterating over the apexFiles list that represents actual files
(not Soong modules) that are included in the APEX. The problem is now
fixed by iterarting the all the modules that directly or indirectly
contribute to the APEX using walkPayloadDeps() function.

Bug: 149455933
Test: m
Change-Id: I38655da62b590b669ab4649815b61a5a8e314154
diff --git a/apex/apex_test.go b/apex/apex_test.go
index babc27b..5468c77 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -168,6 +168,7 @@
 		"vendor/foo/devkeys/testkey.pem":             nil,
 		"NOTICE":                                     nil,
 		"custom_notice":                              nil,
+		"custom_notice_for_static_lib":               nil,
 		"testkey2.avbpubkey":                         nil,
 		"testkey2.pem":                               nil,
 		"myapex-arm64.apex":                          nil,
@@ -372,6 +373,20 @@
 			system_shared_libs: [],
 			stl: "none",
 			notice: "custom_notice",
+			static_libs: ["libstatic"],
+			// TODO: remove //apex_available:platform
+			apex_available: [
+				"//apex_available:platform",
+				"myapex",
+			],
+		}
+
+		cc_library_static {
+			name: "libstatic",
+			srcs: ["mylib.cpp"],
+			system_shared_libs: [],
+			stl: "none",
+			notice: "custom_notice_for_static_lib",
 			// TODO: remove //apex_available:platform
 			apex_available: [
 				"//apex_available:platform",
@@ -470,11 +485,12 @@
 
 	mergeNoticesRule := ctx.ModuleForTests("myapex", "android_common_myapex_image").Rule("mergeNoticesRule")
 	noticeInputs := mergeNoticesRule.Inputs.Strings()
-	if len(noticeInputs) != 2 {
-		t.Errorf("number of input notice files: expected = 2, actual = %q", len(noticeInputs))
+	if len(noticeInputs) != 3 {
+		t.Errorf("number of input notice files: expected = 3, actual = %q", len(noticeInputs))
 	}
 	ensureListContains(t, noticeInputs, "NOTICE")
 	ensureListContains(t, noticeInputs, "custom_notice")
+	ensureListContains(t, noticeInputs, "custom_notice_for_static_lib")
 
 	depsInfo := strings.Split(ctx.ModuleForTests("myapex", "android_common_myapex_image").Output("myapex-deps-info.txt").Args["content"], "\\n")
 	ensureListContains(t, depsInfo, "myjar <- myapex")