c232299f78
This patch adds a new interface that partners must provide to Cdm::initialize(), ILogger. ILogger replaces stderr as the sink to which logging messages are sent. For partners that still want to log to stderr, a reference implementation that logs to stderr is provided. As a side-effect of this, many test-related source files had to be updated to thread the new parameter to Cdm::initialize() through them. This also necessitated adding a new variant of FormatString() that can be called with a va_list directly so it can be called from other functions that take varargs. Bug: 201446862 Merged from https://widevine-internal-review.googlesource.com/177270 Change-Id: Ie31a10162773883b337f3a6144cf180a2b100139