AAPT2: Parse coreApp in <manifest> as boolean

Bug:30751662
Change-Id: I283be5725426ee084944c1921df40d1bd6188028
diff --git a/tools/aapt2/integration-tests/AppOne/AndroidManifest.xml b/tools/aapt2/integration-tests/AppOne/AndroidManifest.xml
index b6d8f2d..1156b01 100644
--- a/tools/aapt2/integration-tests/AppOne/AndroidManifest.xml
+++ b/tools/aapt2/integration-tests/AppOne/AndroidManifest.xml
@@ -14,4 +14,7 @@
      limitations under the License.
 -->
 
-<manifest package="com.android.aapt.app.one" />
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.aapt.app.one" coreApp="true">
+    <uses-sdk android:minSdkVersion="21" />
+</manifest>