AAPT2: Add convert command

This command allows a developer to convert their proto APK
(generated from the link phase using --proto-format) into
a binary APK suitable for use on device.

  aapt2 convert -o output.apk input.apk

Test: manual + make aapt2_tests
Change-Id: I10a7c33bb4b57006d01fe00a8bf92f78e04e7e50
diff --git a/tools/aapt2/xml/XmlDom_test.cpp b/tools/aapt2/xml/XmlDom_test.cpp
index 34e6d3f..e5012d6 100644
--- a/tools/aapt2/xml/XmlDom_test.cpp
+++ b/tools/aapt2/xml/XmlDom_test.cpp
@@ -70,8 +70,7 @@
   ASSERT_TRUE(flattener.Consume(context.get(), doc.get()));
 
   auto block = util::Copy(buffer);
-  std::unique_ptr<XmlResource> new_doc =
-      Inflate(block.get(), buffer.size(), context->GetDiagnostics(), Source("test.xml"));
+  std::unique_ptr<XmlResource> new_doc = Inflate(block.get(), buffer.size(), nullptr);
   ASSERT_THAT(new_doc, NotNull());
 
   EXPECT_THAT(new_doc->root->name, StrEq("Layout"));