Revert "Flush right after writing READ entry."

This reverts commit bcd988b1b71ee6d4af07c2456cdd78ee958fba74.
Don't append to a truncated line in the journal.

Fixes https://github.com/square/okhttp/issues/1099

Conflicts:
	okhttp/src/main/java/com/squareup/okhttp/internal/DiskLruCache.java