Revert the change of converting DCHECK to CHECK.

Now change all things back to DCHECK except for the checking of
IsOffline(). I plan to send this CL to CQ by Sunday so that
the change of converting DCHECK to CHECK will not get into dev version.
This reverts commit 36daac446c9f405322ee6eb9b15ded2675ba6e78.

BUG=273917

Review URL: https://codereview.chromium.org/25109005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225892 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225892
Make media::VideoCaptureImpl::ClientBuffer RefCountedThreadSafe

BUG=298981
TEST=None
TBR=glider

Review URL: https://codereview.chromium.org/25130002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225893 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225893
Fix bug in QuicSocketUtils::GetAddressFromMsghdr.  This bug results
in a bogus peer address being used which then leads to the connection
being torn down because connection migration is not supported.

BUG=297040

Review URL: https://codereview.chromium.org/25141003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225894 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225894