AAPT2: Fixup namespace implementation

A few pieces were missing in the namespace mangling implementation.
Namespace aware libraries now work, along with R class generation.

Bug: 64706588
Test: make AaptTestNamespace_App
Change-Id: I12f78d6aa909e782c0faf7ceaa36058f2e6c864a
diff --git a/tools/aapt2/java/JavaClassGenerator.cpp b/tools/aapt2/java/JavaClassGenerator.cpp
index 44fa0f1..8da9106 100644
--- a/tools/aapt2/java/JavaClassGenerator.cpp
+++ b/tools/aapt2/java/JavaClassGenerator.cpp
@@ -480,7 +480,7 @@
   if (NameMangler::Unmangle(&unmangled_name, &unmangled_package)) {
     // The entry name was mangled, and we successfully unmangled it.
     // Check that we want to emit this symbol.
-    if (package_name != unmangled_package) {
+    if (package_name_to_generate != unmangled_package) {
       // Skip the entry if it doesn't belong to the package we're writing.
       return {};
     }
@@ -579,8 +579,7 @@
         continue;
       }
 
-      // Stay consistent with AAPT and generate an empty type class if the R class
-      // is public.
+      // Stay consistent with AAPT and generate an empty type class if the R class is public.
       const bool force_creation_if_empty =
           (options_.types == JavaClassGeneratorOptions::SymbolTypes::kPublic);