Remove HttpTransactionDelegate and all users (LoadTimeStats).

These metrics are not used anymore.

TEST=builds
BUG=

TBR=mkosiba@chromium.org (webview)

Review URL: https://codereview.chromium.org/121453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242643 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242643
Add TSAN suppression for protential race in GCMClientLoadingCompletedAfterReadingRegistration

Suppress potential race condition found by tsan.

BUG=330903
R=nasko@chromium.org

Review URL: https://codereview.chromium.org/120983005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242644 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242644