Change Cdm::GetCurrentWallTimeMs() to GetCurrentWallTimeInSeconds().

Since pp::Module::Get()->core()->GetTime() returns seconds, not ms.

Also updated clear key system to use CdmHost to implement a simple heart beat system for testing purpose.

BUG=none
TEST=none

Review URL: https://codereview.chromium.org/11340021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@165416 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed