aapt2: Add a new flag '--revision-code'

A new flag to inject revisionCode into the manifest for cts splits tests.

Bug: 174338944
Test: atest aapt2_tests
Change-Id: If5a089f37233f53af3012ca5eab17fab21eafd9c
diff --git a/tools/aapt2/cmd/Link.h b/tools/aapt2/cmd/Link.h
index 852b1244..768b4b2 100644
--- a/tools/aapt2/cmd/Link.h
+++ b/tools/aapt2/cmd/Link.h
@@ -190,8 +190,11 @@
     AddOptionalFlag("--version-name",
         "Version name to inject into the AndroidManifest.xml if none is present.",
         &options_.manifest_fixer_options.version_name_default);
+    AddOptionalFlag("--revision-code",
+        "Revision code (integer) to inject into the AndroidManifest.xml if none is\n"
+            "present.", &options_.manifest_fixer_options.revision_code_default);
     AddOptionalSwitch("--replace-version",
-        "If --version-code and/or --version-name are specified, these\n"
+        "If --version-code, --version-name, and/or --revision-code are specified, these\n"
             "values will replace any value already in the manifest. By\n"
             "default, nothing is changed if the manifest already defines\n"
             "these attributes.",