Revert "Deduplicate APEX variants that would build identically"

This reverts commit d6b2525b003b5620b3745a79dce56093173504f5.

Reason for revert: <Breaks tests - confirmed by Forrest: b/165188843>

Change-Id: I7cb68cb87522415004390c0672dc774e0067b122
diff --git a/java/sdk_library.go b/java/sdk_library.go
index de16173..2aae42f 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -1376,22 +1376,22 @@
 	return android.Paths{jarPath.Path()}
 }
 
-// Get the apex names for module, nil if it is for platform.
-func getApexNamesForModule(module android.Module) []string {
+// Get the apex name for module, "" if it is for platform.
+func getApexNameForModule(module android.Module) string {
 	if apex, ok := module.(android.ApexModule); ok {
-		return apex.InApexes()
+		return apex.ApexVariationName()
 	}
 
-	return nil
+	return ""
 }
 
-// Check to see if the other module is within the same set of named APEXes as this module.
+// Check to see if the other module is within the same named APEX as this module.
 //
 // If either this or the other module are on the platform then this will return
 // false.
-func withinSameApexesAs(module android.ApexModule, other android.Module) bool {
-	names := module.InApexes()
-	return len(names) > 0 && reflect.DeepEqual(names, getApexNamesForModule(other))
+func withinSameApexAs(module android.ApexModule, other android.Module) bool {
+	name := module.ApexVariationName()
+	return name != "" && getApexNameForModule(other) == name
 }
 
 func (module *SdkLibrary) sdkJars(ctx android.BaseModuleContext, sdkVersion sdkSpec, headerJars bool) android.Paths {
@@ -1410,7 +1410,7 @@
 		// Only allow access to the implementation library in the following condition:
 		// * No sdk_version specified on the referencing module.
 		// * The referencing module is in the same apex as this.
-		if sdkVersion.kind == sdkPrivate || withinSameApexesAs(module, ctx.Module()) {
+		if sdkVersion.kind == sdkPrivate || withinSameApexAs(module, ctx.Module()) {
 			if headerJars {
 				return module.HeaderJars()
 			} else {
@@ -1949,7 +1949,7 @@
 	// For consistency with SdkLibrary make the implementation jar available to libraries that
 	// are within the same APEX.
 	implLibraryModule := module.implLibraryModule
-	if implLibraryModule != nil && withinSameApexesAs(module, ctx.Module()) {
+	if implLibraryModule != nil && withinSameApexAs(module, ctx.Module()) {
 		if headerJars {
 			return implLibraryModule.HeaderJars()
 		} else {