AAPT2: Debug::DumpXml display compiled attribute values.

Test: manually dumped a compiled  AndroidManifest.xml file.

Change-Id: I14f022fd1f95693b21d07b7b8c1886f23738242a
diff --git a/tools/aapt2/Debug.cpp b/tools/aapt2/Debug.cpp
index 49ed778..dba9cb5 100644
--- a/tools/aapt2/Debug.cpp
+++ b/tools/aapt2/Debug.cpp
@@ -291,7 +291,13 @@
         std::cerr << "(" << attr.compiled_attribute.value().id.value_or_default(ResourceId(0x0))
                   << ")";
       }
-      std::cerr << "=" << attr.value << "\n";
+      std::cerr << "=";
+      if (attr.compiled_value != nullptr) {
+        std::cerr << *attr.compiled_value;
+      } else {
+        std::cerr << attr.value;
+      }
+      std::cerr << "\n";
     }
 
     prefix_ += "  ";