Reapply "Remove unassigned event log tags feature"

.logtags files are a mapping of an integer -> name. However, there
is an unused feature where you could put a '?' instead of an integer,
and then the build system would assign a number to it, taking care
to avoid all other already-assigned numbers across the source tree.

This feature makes it hard to support some things we're working towards,
like incremental soong and treble common system images, so remove it.

Also modernize the python scripts a little.

The additions since the revert are the cleanups from aosp/3403019, and
removing a missed reference to all-event-log-tags.txt in java.mk.

This reverts commit 078347368de279b41a37b3599e24e60014892fef.

Bug: 382515940
Test: m event-log-tags
Change-Id: I8f08f3286f1275083e2074948f2feb39219f3687

3 files changed, 3 insertions, 38 deletions

diff --git a/android/logtags.go b/android/logtags.go
index 7929057ff..1e92dad68 100644
--- a/android/logtags.go
+++ b/android/logtags.go
@@ -16,41 +16,8 @@ package android
 
 import "github.com/google/blueprint"
 
-func init() {
-	RegisterParallelSingletonType("logtags", LogtagsSingleton)
-}
-
 type LogtagsInfo struct {
 	Logtags Paths
 }
 
 var LogtagsProviderKey = blueprint.NewProvider[*LogtagsInfo]()
-
-func LogtagsSingleton() Singleton {
-	return &logtagsSingleton{}
-}
-
-type logtagsSingleton struct{}
-
-func MergedLogtagsPath(ctx PathContext) OutputPath {
-	return PathForIntermediates(ctx, "all-event-log-tags.txt")
-}
-
-func (l *logtagsSingleton) GenerateBuildActions(ctx SingletonContext) {
-	var allLogtags Paths
-	ctx.VisitAllModules(func(module Module) {
-		if !module.ExportedToMake() {
-			return
-		}
-		if logtagsInfo, ok := OtherModuleProvider(ctx, module, LogtagsProviderKey); ok {
-			allLogtags = append(allLogtags, logtagsInfo.Logtags...)
-		}
-	})
-
-	builder := NewRuleBuilder(pctx, ctx)
-	builder.Command().
-		BuiltTool("merge-event-log-tags").
-		FlagWithOutput("-o ", MergedLogtagsPath(ctx)).
-		Inputs(SortedUniquePaths(allLogtags))
-	builder.Build("all-event-log-tags.txt", "merge logtags")
-}
diff --git a/filesystem/filesystem.go b/filesystem/filesystem.go
index 81afd02b4..9ad2cc9bc 100644
--- a/filesystem/filesystem.go
+++ b/filesystem/filesystem.go
@@ -882,8 +882,7 @@ func (f *filesystem) buildEventLogtagsFile(ctx android.ModuleContext, builder *a
 	eventLogtagsPath := etcPath.Join(ctx, "event-log-tags")
 	builder.Command().Text("mkdir").Flag("-p").Text(etcPath.String())
 	cmd := builder.Command().BuiltTool("merge-event-log-tags").
-		FlagWithArg("-o ", eventLogtagsPath.String()).
-		FlagWithInput("-m ", android.MergedLogtagsPath(ctx))
+		FlagWithArg("-o ", eventLogtagsPath.String())
 
 	for _, path := range android.SortedKeys(logtagsFilePaths) {
 		cmd.Text(path)
diff --git a/java/gen.go b/java/gen.go
index 1b4f4c7dc..aab841851 100644
--- a/java/gen.go
+++ b/java/gen.go
@@ -26,15 +26,14 @@ import (
 )
 
 func init() {
-	pctx.SourcePathVariable("logtagsCmd", "build/make/tools/java-event-log-tags.py")
-	pctx.SourcePathVariable("logtagsLib", "build/make/tools/event_log_tags.py")
+	pctx.HostBinToolVariable("logtagsCmd", "java-event-log-tags")
 }
 
 var (
 	logtags = pctx.AndroidStaticRule("logtags",
 		blueprint.RuleParams{
 			Command:     "$logtagsCmd -o $out $in",
-			CommandDeps: []string{"$logtagsCmd", "$logtagsLib"},
+			CommandDeps: []string{"$logtagsCmd"},
 		})
 )