Exclude TraceEventTestFixture.TraceContinuousSampling and MessageLoopTestTypeUI.RecursiveDenial3 from Dr. Memory runs as both tests are flaky (both are already excluded under tsan).

TBR=zhaoqin@chromium.org
BUG=308273,93843

Review URL: https://codereview.chromium.org/147343002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246987 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246987