Create new project appsearch:appsearch-play-services-storage.

This allows 1p/3p apps PlatformStorage functionality on pre-S devices
and provide implementations for AppSearchSession and
GlobalSearchSession using play-services-appsearch SDK.

Bug: 274022965
Test: Code and tests will be added in later CLs
Relnote: N/A
Change-Id: Ie502345e891e1269b4866f37b4ab37704535709d
diff --git a/settings.gradle b/settings.gradle
index afb8ca2..db6aa70 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -380,6 +380,7 @@
 includeProject(":appsearch:appsearch-ktx", [BuildType.MAIN])
 includeProject(":appsearch:appsearch-local-storage", [BuildType.MAIN])
 includeProject(":appsearch:appsearch-platform-storage", [BuildType.MAIN])
+includeProject(":appsearch:appsearch-play-services-storage", [BuildType.MAIN])
 includeProject(":appsearch:appsearch-test-util", [BuildType.MAIN])
 includeProject(":arch:core:core-common", [BuildType.MAIN, BuildType.FLAN, BuildType.WEAR, BuildType.COMPOSE, BuildType.CAMERA])
 includeProject(":arch:core:core-runtime", [BuildType.MAIN, BuildType.FLAN, BuildType.WEAR, BuildType.COMPOSE, BuildType.CAMERA])