Revert "Revert "Build notice files from license metadata.""

This reverts commit 77807b3c277723161a193aea2a9df1e464448c3d.

Reason for revert: fix and roll forward again

Change-Id: I80c796ca81ecf29df9522babe54d684a0d11b9e6
diff --git a/apex/androidmk.go b/apex/androidmk.go
index 059b4d7..e094a12 100644
--- a/apex/androidmk.go
+++ b/apex/androidmk.go
@@ -396,10 +396,6 @@
 				}
 				a.writeRequiredModules(w, moduleNames)
 
-				if a.mergedNotices.Merged.Valid() {
-					fmt.Fprintln(w, "LOCAL_NOTICE_FILE :=", a.mergedNotices.Merged.Path().String())
-				}
-
 				fmt.Fprintln(w, "include $(BUILD_PREBUILT)")
 
 				if apexType == imageApex {
diff --git a/apex/apex.go b/apex/apex.go
index 6d8a67a..cb88f02 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -414,8 +414,8 @@
 	// Processed file_contexts files
 	fileContexts android.WritablePath
 
-	// Struct holding the merged notice file paths in different formats
-	mergedNotices android.NoticeOutputs
+	// Path to notice file in html.gz format.
+	htmlGzNotice android.WritablePath
 
 	// The built APEX file. This is the main product.
 	// Could be .apex or .capex
@@ -487,11 +487,10 @@
 // for each of the files in case when the APEX is flattened.
 type apexFile struct {
 	// buildFile is put in the installDir inside the APEX.
-	builtFile   android.Path
-	noticeFiles android.Paths
-	installDir  string
-	customStem  string
-	symlinks    []string // additional symlinks
+	builtFile  android.Path
+	installDir string
+	customStem string
+	symlinks   []string // additional symlinks
 
 	// Info for Android.mk Module name of `module` in AndroidMk. Note the generated AndroidMk
 	// module for apexFile is named something like <AndroidMk module name>.<apex name>[<apex
@@ -528,7 +527,6 @@
 		module:              module,
 	}
 	if module != nil {
-		ret.noticeFiles = module.NoticeFiles()
 		ret.moduleDir = ctx.OtherModuleDir(module)
 		ret.requiredModuleNames = module.RequiredModuleNames()
 		ret.targetRequiredModuleNames = module.TargetRequiredModuleNames()
diff --git a/apex/apex_test.go b/apex/apex_test.go
index 85bd595..ec815c4 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -591,15 +591,6 @@
 		t.Errorf("Could not find all expected symlinks! foo: %t, foo_link_64: %t. Command was %s", found_foo, found_foo_link_64, copyCmds)
 	}
 
-	mergeNoticesRule := ctx.ModuleForTests("myapex", "android_common_myapex_image").Rule("mergeNoticesRule")
-	noticeInputs := mergeNoticesRule.Inputs.Strings()
-	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")
-
 	fullDepsInfo := strings.Split(ctx.ModuleForTests("myapex", "android_common_myapex_image").Output("depsinfo/fulllist.txt").Args["content"], "\\n")
 	ensureListContains(t, fullDepsInfo, "  myjar(minSdkVersion:(no version)) <- myapex")
 	ensureListContains(t, fullDepsInfo, "  mylib2(minSdkVersion:(no version)) <- mylib")
diff --git a/apex/builder.go b/apex/builder.go
index 8c5f99b..50c8dd1 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -305,32 +305,6 @@
 	return output.OutputPath
 }
 
-// buildNoticeFiles creates a buile rule for aggregating notice files from the modules that
-// contributes to this APEX. The notice files are merged into a big notice file.
-func (a *apexBundle) buildNoticeFiles(ctx android.ModuleContext, apexFileName string) android.NoticeOutputs {
-	var noticeFiles android.Paths
-
-	a.WalkPayloadDeps(ctx, func(ctx android.ModuleContext, from blueprint.Module, to android.ApexModule, externalDep bool) bool {
-		if externalDep {
-			// As soon as the dependency graph crosses the APEX boundary, don't go further.
-			return false
-		}
-		noticeFiles = append(noticeFiles, to.NoticeFiles()...)
-		return true
-	})
-
-	// TODO(jiyong): why do we need this? WalkPayloadDeps should have already covered this.
-	for _, fi := range a.filesInfo {
-		noticeFiles = append(noticeFiles, fi.noticeFiles...)
-	}
-
-	if len(noticeFiles) == 0 {
-		return android.NoticeOutputs{}
-	}
-
-	return android.BuildNoticeOutput(ctx, a.installDir, apexFileName, android.SortedUniquePaths(noticeFiles))
-}
-
 // buildInstalledFilesFile creates a build rule for the installed-files.txt file where the list of
 // files included in this APEX is shown. The text file is dist'ed so that people can see what's
 // included in the APEX without actually downloading and extracting it.
@@ -642,12 +616,11 @@
 			optFlags = append(optFlags, "--logging_parent ", a.overridableProperties.Logging_parent)
 		}
 
-		a.mergedNotices = a.buildNoticeFiles(ctx, a.Name()+suffix)
-		if a.mergedNotices.HtmlGzOutput.Valid() {
-			// If there's a NOTICE file, embed it as an asset file in the APEX.
-			implicitInputs = append(implicitInputs, a.mergedNotices.HtmlGzOutput.Path())
-			optFlags = append(optFlags, "--assets_dir "+filepath.Dir(a.mergedNotices.HtmlGzOutput.String()))
-		}
+		// Create a NOTICE file, and embed it as an asset file in the APEX.
+		a.htmlGzNotice = android.PathForModuleOut(ctx, "NOTICE", "NOTICE.html.gz")
+		android.BuildNoticeHtmlOutputFromLicenseMetadata(ctx, a.htmlGzNotice)
+		implicitInputs = append(implicitInputs, a.htmlGzNotice)
+		optFlags = append(optFlags, "--assets_dir "+filepath.Dir(a.htmlGzNotice.String()))
 
 		if (moduleMinSdkVersion.GreaterThan(android.SdkVersion_Android10) && !a.shouldGenerateHashtree()) && !compressionEnabled {
 			// Apexes which are supposed to be installed in builtin dirs(/system, etc)