Make change and version bump to r_aml_300900300 for mainline module file: manifest.json

Change-Id: I43023f07276f023d7f6ff9ab6e8edb974560d93e
diff --git a/manifest.json b/manifest.json
index a06d5e9..0ab3b41 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,4 +1,4 @@
 {
   "name": "com.android.sdkext",
-  "version": 300900200
+  "version": 300900300
 }