Version bump to PPB1.180905.004

Change-Id: Ia03b21fb90511280058e9a8988e56939b50a8ca2
diff --git a/core/build_id.mk b/core/build_id.mk
index a28a753..7a87cf0 100644
--- a/core/build_id.mk
+++ b/core/build_id.mk
@@ -18,4 +18,4 @@
 # (like "CRB01").  It must be a single word, and is
 # capitalized by convention.
 
-export BUILD_ID=PPB1.180905.003
+export BUILD_ID=PPB1.180905.004