Allow to tag owner to PRODUCT_COPY_FILES

PRODUCT_COPY_FILES now is a list of words like <source
path>:<destination path>[:<owner>].
The optional :<owner> is used to indicate the owner of a vendor file.

Bug: 7048854
Change-Id: I435d1e18b7a091fb62513062cfc2e420e51557ec
diff --git a/core/Makefile b/core/Makefile
index 8f0895b..e0f6da8 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -13,7 +13,7 @@
 
 # -----------------------------------------------------------------
 # Define rules to copy PRODUCT_COPY_FILES defined by the product.
-# PRODUCT_COPY_FILES contains words like <source file>:<dest file>.
+# PRODUCT_COPY_FILES contains words like <source file>:<dest file>[:<owner>].
 # <dest file> is relative to $(PRODUCT_OUT), so it should look like,
 # e.g., "system/etc/file.xml".
 # The filter part means "only eval the copy-one-file rule if this