Create two new test modules for media2-session version-compat-test

As a first step for creating version-compat-test, this CL copies two
existing modules (client, previous) with adding the postfix
'-previous' to the names of the modules.

This CL also replaces a test image ("big_buck_bunny.jpg")
with a smaller one.

Bug: 134372941
Test: Builds successfully
Change-Id: I0fa0a06aea2227698b70b14203582317a41ac387
diff --git a/settings.gradle b/settings.gradle
index 2ee4381..8e42dc6 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -280,7 +280,9 @@
 includeProject(":support-media-compat-test-lib", "media/version-compat-tests/lib")
 
 includeProject(":support-media2-test-client", "media2/session/version-compat-tests/current/client")
+includeProject(":support-media2-test-client-previous", "media2/session/version-compat-tests/previous/client")
 includeProject(":support-media2-test-service", "media2/session/version-compat-tests/current/service")
+includeProject(":support-media2-test-service-previous", "media2/session/version-compat-tests/previous/service")
 includeProject(":support-media2-test-common", "media2/session/version-compat-tests/common")
 
 /////////////////////////////